Neglected tropical diseases Health Dictionary

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Neglected Tropical Diseases: From 1 Different Sources

(NTDs) as defined by the *World Health Organization (WHO), a diverse group of *communicable diseases found almost entirely among poor populations in tropical and subtropical parts of Africa, Asia, and the Americas. Although they affect more than 1.4 billion people, and countermeasures would in many cases be inexpensive, NTDs have traditionally received far less attention than the major infectious diseases HIV/AIDS, tuberculosis, and malaria. In 2013 the WHO resolved to intensify its efforts to eradicate or control NTDs. The current WHO list identifies 24 such diseases, including *Buruli ulcer, *chikungunya fever, *dengue, *leishmaniasis, and *Madura foot (mycetoma).
Health Source: Oxford | Concise Colour Medical Dictionary
Author: Jonathan Law, Elizabeth Martin

Tropical Ulcer

A cutaneous ulcer seen particularly in malnourished individuals. The cause of these ulcers is often ascribed to a synergistic infection by the spirochaete Treponema vincentii and the anaerobic Gram negative rod, Fusobacterium nucleatum.... tropical ulcer

Collagen Diseases

A group of diseases affecting CONNECTIVE TISSUE. The term is really outdated since there is no evidence that collagen is primarily involved. Fibrinoid NECROSIS and VASCULITIS are two ‘characteristics’, and autoimmunity reaction may occur in the connective tissue. The latter affects blood vessels and causes secondary damage in the connective tissue. Such conditions are sometimes described as collagen vascular diseases, examples being RHEUMATOID ARTHRITIS, SYSTEMIC LUPUS ERYTHEMATOSUS (SLE), and SCLERODERMA.... collagen diseases

Tropical Medicine

In simple terms, tropical medicine is the medicine practised in the tropics. It arose as a discipline in the 19th century when physicians responsible for the health of colonists and soldiers from the dominant, European countries were faced with diseases not encountered in temperate climates. With extensive worldwide travel possible today, tropical diseases are now being widely seen in returning travellers and expatriates.... tropical medicine

Prescribed Diseases

A collection of industrial diseases which provide those with a disease legal entitlement to welfare bene?ts. Examples are DEAFNESS from excessive noise in the workplace; ANTHRAX from farming; PNEUMOCONIOSIS from industrially generated dust (coal mining); and LEAD POISONING from the handling of chemicals. (See also OCCUPATIONAL HEALTH, MEDICINE AND DISEASES.)... prescribed diseases

Venereal Diseases

See SEXUALLY TRANSMITTED DISEASES (STDS).... venereal diseases

Tropical Diseases

Technically, those diseases occurring in the area of the globe situated between the Tropic of Cancer and the Tropic of Capricorn: pertaining to the sun. They include many ‘exotic’ infections – many of them parasitic in origin – which fall under the umbrella of ‘TROPICAL MEDICINE’. However, disease in the tropics is far broader than this and includes numerous other infections, many of them with a viral or bacterial basis: for example, the viral hepatidises, streptococcal and pneumococcal infections, and tuberculosis. The prevalence of other diseases, such as rheumatic cardiac disease, cirrhosis, heptocellular carcinoma (‘hepatoma’), and various nutrition-related problems, is also much increased in most areas of the tropics. With people from developed countries increasingly travelling to worldwide destinations for business and holiday, the ‘importation’ of tropical diseases to temperate climates should be borne in mind when people fall ill.

The following diseases and conditions are treated under their separate dictionary entries: ANCYLOSTOMIASIS; BERIBERI; BLACKWATER FEVER; CHOLERA; DENGUE; DRACONTIASIS; DYSENTERY; ELEPHANTIASIS; FILARIASIS; HEAT STROKE; LEISHMANIASIS; LEPROSY; LIVER, DISEASES OF; MALARIA; ORIENTAL SORE; PLAGUE; PRICKLY HEAT; SCHISTOSOMIASIS; SLEEPING SICKNESS; STRONGYLOIDIASIS; SUNBURN; YAWS; YELLOW FEVER.... tropical diseases

Tropical Medicinal Plants

Tropical countries are a treasure house of a wide variety of medicinal plants. Some species are found wild, while a number of species have been domesticated by the farmers. Many species have been grown in homesteads and become part of traditional home remedies. A limited number of species are commercially cultivated though a few more have potential for large-scale production. The important tropical and subtropical medicinal plants are discussed here highlighting the importance, medicinal and other uses, distribution, botany, agrotechnology, chemical constituents and activity. For practical convenience of the discussion in this book, they are classified under the following four broad groups.

a) Medicinal herbs

b) Medicinal shrubs

c) Medicinal climbers

d)Medicinal trees... tropical medicinal plants

Notifiable Diseases

Notifiable diseases under the Public Health (Control of Disease Act, 1984) are:–

Acute encephalitis, acute meningitis, acute poliomyelitis, anthrax, cholera, diphtheria, dysentery (amoebic and bacillary), food poisoning, infective jaundice, leprosy, leptospirosis, lassa fever, mumps, malaria, marburg disease, measles, German measles, ophthalmia neonatorum, paratyphoid fever, plague, rabies, relapsing fever, scarlet fever, smallpox, tetanus, tuberculosis, typhoid fever, typhus, viral haemorrhagic fever, whooping cough and yellow fever.

Six communicable diseases are internationally notifiable to the World Health Organisation: yellow fever, plague, cholera, smallpox, louse-borne relapsing fever, louse-borne typhus.

Notification has to be made to local and central Government authorities. Certain occupational diseases and all cases of cancer must be registered and notified.

It is required that the above diseases and certain others receive modern medical therapy in a hospital or treatment under the supervision of a qualified physician. Failure to conform may expose a practitioner, registered or unregistered, to a charge of negligence. ... notifiable diseases

Abdomen, Diseases Of

See under STOMACH, DISEASES OF; INTESTINE, DISEASES OF; DIARRHOEA; LIVER, DISEASES OF; PANCREAS, DISEASES OF; GALL-BLADDER, DISEASES OF; KIDNEYS, DISEASES OF; URINARY BLADDER, DISEASES OF; HERNIA; PERITONITIS; APPENDICITIS; TUMOUR.

Various processes that can occur include in?ammation, ulceration, infection or tumour. Abdominal disease may be of rapid onset, described as acute, or more long-term when it is termed chronic.

An ‘acute abdomen’ is most commonly caused by peritonitis – in?ammation of the membrane that lines the abdomen. If any structure in the abdomen gets in?amed, peritonitis may result. Causes include injury, in?ammation of the Fallopian tubes (SALPINGITIS), and intestinal disorders such as APPENDICITIS, CROHN’S DISEASE, DIVERTICULITIS or a perforated PEPTIC ULCER. Disorders of the GALLBLADDER or URINARY TRACT may also result in acute abdominal pain.

General symptoms of abdominal disease include:

Pain This is usually ill-de?ned but can be very unpleasant, and is termed visceral pain. Pain is initially felt near the mid line of the abdomen. Generally, abdominal pain felt high up in the mid line originates from the stomach and duodenum. Pain that is felt around the umbilicus arises from the small intestine, appendix and ?rst part of the large bowel, and low mid-line pain comes from the rest of the large bowel. If the diseased organ secondarily in?ames or infects the lining of the abdominal wall – the PERITONEUM – peritonitis occurs and the pain becomes more de?ned and quite severe, with local tenderness over the site of the diseased organ itself. Hence the pain of appendicitis begins as a vague mid-line pain, and only later moves over to the right iliac fossa, when the in?amed appendix has caused localised peritonitis. PERFORATION of one of the hollow organs in the abdomen – for example, a ruptured appendix or a gastric or duodenal ulcer (see STOMACH, DISEASES OF) eroding the wall of the gut – usually causes peritonitis with resulting severe pain.

The character of the pain is also important. It may be constant, as occurs in in?ammatory diseases and infections, or colicky (intermittent) as in intestinal obstruction.

Swelling The commonest cause of abdominal swelling in women is pregnancy. In disease, swelling may be due to the accumulation of trapped intestinal contents within the bowel, the presence of free ?uid (ascites) within the abdomen, or enlargement of one or more of the abdominal organs due to benign causes or tumour.

Constipation is the infrequent or incomplete passage of FAECES; sometimes only ?atus can be passed and, rarely, no bowel movements occur (see main entry for CONSTIPATION). It is often associated with abdominal swelling. In intestinal obstruction, the onset of symptoms is usually rapid with complete constipation and severe, colicky pain. In chronic constipation, the symptoms occur more gradually.

Nausea and vomiting may be due to irritation of the stomach, or to intestinal obstruction when it may be particularly foul and persistent. There are also important non-abdominal causes, such as in response to severe pain or motion sickness.

Diarrhoea is most commonly due to simple and self-limiting infection, such as food poisoning, but may also indicate serious disease, especially if it is persistent or contains blood (see main entry for DIARRHOEA).

Jaundice is a yellow discoloration of the skin and eyes, and may be due to disease in the liver or bile ducts (see main entry for JAUNDICE).

Diagnosis and treatment Abdominal diseases are often di?cult to diagnose because of the multiplicity of the organs contained within the abdomen, their inconstant position and the vagueness of some of the symptoms. Correct diagnosis usually requires experience, often supplemented by specialised investigations such as ULTRASOUND. For this reason sufferers should obtain medical advice at an early stage, particularly if the symptoms are severe, persistent, recurrent, or resistant to simple remedies.... abdomen, diseases of

Anus, Diseases Of

See under RECTUM, DISEASES OF.... anus, diseases of

Arteries, Diseases Of

ARTERIES are the blood vessels that convey blood away from the heart to the tissues. The commonest cause of arterial disease is a degenerative condition known as atherosclerosis. Less commonly, in?ammation of the arteries occurs; this in?ammation is known as arteritis and occurs in a variety of conditions.

Atherosclerosis is due to the deposition of CHOLESTEROL into the walls of arteries. The process starts in childhood with the development of fatty streaks lining the arteries. In adulthood these progress, scarring and calcifying to form irregular narrowings within the arteries and eventually leading to blockage of the vessel. The consequence of the narrowing or blockage depends on which vessels are involved

– diseased cerebral vessels cause strokes; coronary vessels cause angina and heart attacks; renal vessels cause renal failure; and peripheral arteries cause limb ischaemia (localised bloodlessness).

Risk factors predisposing individuals to atherosclerosis include age, male gender, raised plasma cholesterol concentration, high blood pressure, smoking, a family history of atherosclerosis, diabetes and obesity.

Arteritis occurs in a variety of conditions that produce in?ammation in the arteries. Examples include syphilis – now rare in Britain

– which produces in?ammation of the aorta with subsequent dilatation (aneurysm formation) and risk of rupture; giant cell arteritis (temporal arteritis), a condition usually affecting the elderly, which involves the cranial arteries and leads to headache, tenderness over the temporal arteries and the risk of sudden blindness; Takayasu’s syndrome, predominantly affecting young females, which involves the aortic arch and its major branches, leading to the absence of pulse in affected vessels; and polyarteritis nodosa, a condition causing multiple small nodules to form on the smaller arteries. General symptoms such as fever, malaise, weakness, anorexia and weight loss are accompanied by local manifestations of ischaemia (bloodlessness) in di?erent parts of the body.... arteries, diseases of

Bladder, Diseases Of

See URINARY BLADDER, DISEASES OF and GALLBLADDER, DISEASES OF; see also URINE.... bladder, diseases of

Blood, Diseases Of

See ANAEMIA; LEUKAEMIA; LYMPHOMA; MYELOMATOSIS; THROMBOSIS.... blood, diseases of

Brain, Diseases Of

These consist either of expanding masses (lumps or tumours), or of areas of shrinkage (atrophy) due to degeneration, or to loss of blood supply, usually from blockage of an artery.

Tumours All masses cause varying combinations of headache and vomiting – symptoms of raised pressure within the inexpansible bony box formed by the skull; general or localised epileptic ?ts; weakness of limbs or disordered speech; and varied mental changes. Tumours may be primary, arising in the brain, or secondary deposits from tumours arising in the lung, breast or other organs. Some brain tumours are benign and curable by surgery: examples include meningiomas and pituitary tumours. The symptoms depend on the size and situation of the mass. Abscesses or blood clots (see HAEMATOMA) on the surface or within the brain may resemble tumours; some are removable. Gliomas ( see GLIOMA) are primary malignant tumours arising in the glial tissue (see GLIA) which despite surgery, chemotherapy and radiotherapy usually have a bad prognosis, though some astrocytomas and oligodendronogliomas are of low-grade malignancy. A promising line of research in the US (in the animal-testing stage in 2000) suggests that the ability of stem cells from normal brain tissue to ‘home in’ on gliomal cells can be turned to advantage. The stem cells were chemically manipulated to carry a poisonous compound (5-?uorouracil) to the gliomal cells and kill them, without damaging normal cells. Around 80 per cent of the cancerous cells in the experiments were destroyed in this way.

Clinical examination and brain scanning (CT, or COMPUTED TOMOGRAPHY; magnetic resonance imaging (MRI) and functional MRI) are safe, accurate methods of demonstrating the tumour, its size, position and treatability.

Strokes When a blood vessel, usually an artery, is blocked by a clot, thrombus or embolism, the local area of the brain fed by that artery is damaged (see STROKE). The resulting infarct (softening) causes a stroke. The cells die and a patch of brain tissue shrinks. The obstruction in the blood vessel may be in a small artery in the brain, or in a larger artery in the neck. Aspirin and other anti-clotting drugs reduce recurrent attacks, and a small number of people bene?t if a narrowed neck artery is cleaned out by an operation – endarterectomy. Similar symptoms develop abruptly if a blood vessel bursts, causing a cerebral haemorrhage. The symptoms of a stroke are sudden weakness or paralysis of the arm and leg of the opposite side to the damaged area of brain (HEMIPARESIS), and sometimes loss of half of the ?eld of vision to one side (HEMIANOPIA). The speech area is in the left side of the brain controlling language in right-handed people. In 60 per cent of lefthanders the speech area is on the left side, and in 40 per cent on the right side. If the speech area is damaged, diffculties both in understanding words, and in saying them, develops (see DYSPHASIA).

Degenerations (atrophy) For reasons often unknown, various groups of nerve cells degenerate prematurely. The illness resulting is determined by which groups of nerve cells are affected. If those in the deep basal ganglia are affected, a movement disorder occurs, such as Parkinson’s disease, hereditary Huntington’s chorea, or, in children with birth defects of the brain, athetosis and dystonias. Modern drugs, such as DOPAMINE drugs in PARKINSONISM, and other treatments can improve the symptoms and reduce the disabilities of some of these diseases.

Drugs and injury Alcohol in excess, the abuse of many sedative drugs and arti?cial brain stimulants – such as cocaine, LSD and heroin (see DEPENDENCE) – can damage the brain; the effects can be reversible in early cases. Severe head injury can cause localised or di?use brain damage (see HEAD INJURY).

Cerebral palsy Damage to the brain in children can occur in the uterus during pregnancy, or can result from rare hereditary and genetic diseases, or can occur during labour and delivery. Severe neurological illness in the early months of life can also cause this condition in which sti? spastic limbs, movement disorders and speech defects are common. Some of these children are learning-disabled.

Dementias In older people a di?use loss of cells, mainly at the front of the brain, causes ALZHEIMER’S DISEASE – the main feature being loss of memory, attention and reasoned judgement (dementia). This affects about 5 per cent of the over-80s, but is not simply due to ageing processes. Most patients require routine tests and brain scanning to indicate other, treatable causes of dementia.

Response to current treatments is poor, but promising lines of treatment are under development. Like Parkinsonism, Alzheimer’s disease progresses slowly over many years. It is uncommon for these diseases to run in families. Multiple strokes can cause dementia, as can some organic disorders such as cirrhosis of the liver.

Infections in the brain are uncommon. Viruses such as measles, mumps, herpes, human immunode?ciency virus and enteroviruses may cause ENCEPHALITIS – a di?use in?ammation (see also AIDS/HIV).

Bacteria or viruses may infect the membrane covering the brain, causing MENINGITIS. Viral meningitis is normally a mild, self-limiting infection lasting only a few days; however, bacterial meningitis – caused by meningococcal groups B and C, pneumococcus, and (now rarely) haemophilus – is a life-threatening condition. Antibiotics have allowed a cure or good control of symptoms in most cases of meningitis, but early diagnosis is essential. Severe headaches, fever, vomiting and increasing sleepiness are the principal symptoms which demand urgent advice from the doctor, and usually admission to hospital. Group B meningococcus is the commonest of the bacterial infections, but Group C causes more deaths. A vaccine against the latter has been developed and has reduced the incidence of cases by 75 per cent.

If infection spreads from an unusually serious sinusitis or from a chronically infected middle ear, or from a penetrating injury of the skull, an abscess may slowly develop. Brain abscesses cause insidious drowsiness, headaches, and at a late stage, weakness of the limbs or loss of speech; a high temperature is seldom present. Early diagnosis, con?rmed by brain scanning, is followed by antibiotics and surgery in hospital, but the outcome is good in only half of affected patients.

Cerebral oedema Swelling of the brain can occur after injury, due to engorgement of blood vessels or an increase in the volume of the extravascular brain tissue due to abnormal uptake of water by the damaged grey (neurons) matter and white (nerve ?bres) matter. This latter phenomenon is called cerebral oedema and can seriously affect the functioning of the brain. It is a particularly dangerous complication following injury because sometimes an unconscious person whose brain is damaged may seem to be recovering after a few hours, only to have a major relapse. This may be the result of a slow haemorrhage from damaged blood vessels raising intracranial pressure, or because of oedema of the brain tissue in the area surrounding the injury. Such a development is potentially lethal and requires urgent specialist treatment to alleviate the rising intracranial pressure: osmotic agents (see OSMOSIS) such as mannitol or frusemide are given intravenously to remove the excess water from the brain and to lower intracranial pressure, buying time for de?nitive investigation of the cranial damage.... brain, diseases of

Breasts, Diseases Of

The female breasts may be expected to undergo hormone-controlled enlargement at puberty, and later in pregnancy, and the glandular part of the breast undergoes evolution (shrinkage) after the menopause. The breast can also be affected by many di?erent diseases, with common symptoms being pain, nipple discharge or retraction, and the formation of a lump within the breast.

Benign disease is much more common than cancer, particularly in young women, and includes acute in?ammation of the breast (mastitis); abscess formation; and benign breast lumps, which may be ?broadenosis – di?use lumpiness also called chronic mastitis or ?brocystic disease – in which one or more ?uid-?lled sacs (cysts) develop.

Women who are breast feeding are particularly prone to mastitis, as infection may enter the breast via the nipple. The process may be arrested before a breast abscess forms by prompt treatment with antibiotics. Non-bacterial in?ammation may result from mammary duct ectasia (dilatation), in which abnormal or

blocked ducts may over?ow. Initial treatments should be with antibiotics, but if an abscess does form it should be surgically drained.

Duct ectasia, with or without local mastitis, is the usual benign cause of various nipple complaints, with common symptoms being nipple retraction, discharge and skin change.

Breast lumps form the chief potential danger and may be either solid or cystic. Simple examination may fail to distinguish the two types, but aspiration of a benign cyst usually results in its disappearance. If the ?uid is bloodstained, or if a lump still remains, malignancy is possible, and all solid lumps need histological (tissue examination) or cytological (cell examination) assessment. As well as having their medical and family history taken, any women with a breast lump should undergo triple assessment: a combination of clinical examination, imaging

– mammography for the over-35s and ultrasonagraphy for the under-35s – and ?ne-needle aspiration. The medical history should include details of any previous lumps, family history (up to 10 per cent of breast cancer in western countries is due to genetic disposition), pain, nipple discharge, change in size related to menstrual cycle and parous state, and any drugs being taken by the patient. Breasts should be inspected with the arms up and down, noting position, size, consistency, mobility, ?xity, and local lymphadenopathy (glandular swelling). Nipples should be examined for the presence of inversion or discharge. Skin involvement (peau d’orange) should be noted, and, in particular, how long changes have been present. Fine-needle aspiration and cytological examination of the ?uid are essential with ULTRASOUND, MAMMOGRAPHY and possible BIOPSY being considered, depending on the patient’s age and the extent of clinical suspicion that cancer may be present.

The commonest solid benign lump is a ?broadenoma, particularly in women of childbearing age, and is a painless, mobile lump. If small, it is usually safe to leave it alone, provided that the patient is warned to seek medical advice if its size or character changes or if the lump becomes painful. Fibroadenosis (di?use lumpiness often in the upper, outer quadrant) is a common (benign) lump. Others include periductal mastitis, fat NECROSIS, GALACTOCELE, ABSCESS, and non-breast-tissue lumps – for example, a LIPOMA (fatty tissue) or SEBACEOUS CYST. A woman with breast discharge should have a mammograph, ductograph, or total duct excision until the cause of any underlying duct ectasia is known. Appropriate treatment should then be given.

Malignant disease most commonly – but not exclusively – occurs in post-menopausal women, classically presenting as a slowly growing, painless, ?rm lump. A bloodstained nipple discharge or eczematous skin change may also be suggestive of cancer.

The most commonly used classi?cation of invasive cancers has split them into two types, ductal and lobular, but this is no longer suitable. There are also weaknesses in the tumour node metastases (TNM) system and the International Union Against Cancer (UICC) classi?cation.

The TNM system – which classi?es the lump by size, ?xity and presence of affected axillary glands and wider metastatic spread – is best combined with a pathological classi?cation, when assessing the seriousness of a possibly cancerous lump. Risk factors for cancer include nulliparity (see NULLIPARA), ?rst pregnancy over the age of 30 years, early MENARCHE, late MENOPAUSE and positive family history. The danger should be considered in women who are not breast feeding or with previous breast cancer, and must be carefully excluded if the woman is taking any contraceptive steroids or is on hormone-replacement therapy (see under MENOPAUSE).

Screening programmes involving mammography are well established, the aim being to detect more tumours at an early and curable stage. Pick-up rate is ?ve per 1,000 healthy women over 50 years. Yearly two-view mammograms could reduce mortality by 40 per cent but may cause alarm because there are ten false positive mammograms for each true positive result. In premenopausal women, breasts are denser, making mammograms harder to interpret, and screening appears not to save lives. About a quarter of women with a palpable breast lump turn out to have cancer.

Treatment This remains controversial, and all options should be carefully discussed with the patient and, where appropriate, with her partner. Locally contained disease may be treated by local excision of the lump, but sampling of the glands of the armpit of the same side should be performed to check for additional spread of the disease, and hence the need for CHEMOTHERAPY or RADIOTHERAPY. Depending on the extent of spread, simple mastectomy or modi?ed radical mastectomy (which removes the lymph nodes draining the breast) may be required. Follow-up chemotherapy, for example, with TAMOXIFEN (an oestrogen antagonist), much improves survival (it saves 12 lives over 100 women treated), though it may occasionally cause endometrial carcinoma. Analysis in the mid-1990s of large-scale international studies of breast-cancer treatments showed wide variations in their e?ectiveness. As a result the NHS has encouraged hospitals to set up breast-treatment teams containing all the relevant health professional experts and to use those treatments shown to be most e?ective.

As well as the physical treatments provided, women with suspected or proven breast cancer should be o?ered psychological support because up to 30 per cent of affected women develop an anxiety state or depressive illness within a year of diagnosis. Problems over body image and sexual diffculties occur in and around one-quarter of patients. Breast conservation and reconstructive surgery can improve the physical effects of mastectomy, and women should be advised on the prostheses and specially designed brassieres that are available. Specialist nurses and self-help groups are invaluable in supporting affected women and their partners with the problems caused by breast cancer and its treatment. Breast Cancer Care, British Association of Cancer United Patients (BACUP), Cancerlink, and Cancer Relief Macmillan Fund are among voluntary organisations providing support.... breasts, diseases of

Communicable Diseases Control

The control of disease caused by infectious agents or their toxic products. Successes in the 19th and 20th centuries in the treatment and control of communicable diseases such as SMALLPOX, CHOLERA, TUBERCULOSIS, gastrointestinal infections, POLIOMYELITIS and SEXUALLY TRANSMITTED DISEASES (STDS) resulted in an erroneous conception that they no longer posed a serious threat to public health, and certainly not in developed countries. As a consequence, the maintenance of e?ective public health strategies steadily lost out in the competition for resources to the more ‘glamorous’ developments in medicine, such as improved CANCER treatments, HEART surgery, kidney DIALYSIS and organ TRANSPLANTATION. However, in recent decades the dangers of this approach have become increasingly apparent. Rapidly expanding urban populations, more complex lifestyles, new and resurgent infections (some linked to a spread of antibiotic resistance) such as AIDS/HIV and variant CREUTZFELDT-JAKOB DISEASE (CJD), and the ease with which infection can be spread by the enormous growth of long-distance travel and population migrations are severely straining existing public health measures. The supply of clean water, e?ective waste- and sewage-disposal measures, the hygienic production and delivery of food and early detection and subsequent prevention of infectious diseases can no longer be taken for granted. Governments will need to strengthen the provision of workable, properly resourced public health facilities, and developing countries will need ?nancial support and expert help from developed nations to achieve this objective. Timely recognition of new and resurgent infectious diseases requires national and international early-warning mechanisms to ensure rapid investigation and implementation of e?ective control measures. Otherwise, serious breakdowns in public health will occur, and international co-operation is vital to provide and support control measures. (See also COMMUNICABLE DISEASE; NOTIFIABLE DISEASES.)... communicable diseases control

Ear, Diseases Of

Diseases may affect the EAR alone or as part of a more generalised condition. The disease may affect the outer, middle or inner ear or a combination of these.

Examination of the ear includes inspection of the external ear. An auriscope is used to examine the external ear canal and the ear drum. If a more detailed inspection is required, a microscope may be used to improve illumination and magni?cation.

Tuning-fork or Rinne tests are performed to identify the presence of DEAFNESS. The examiner tests whether the vibrating fork is audible at the meatus, and then the foot of the fork is placed on the mastoid bone of the ear to discover at which of the two sites the patient can hear the vibrations for the longest time. This can help to di?erentiate between conductive and nerve deafness.

Hearing tests are carried out to determine the level of hearing. An audiometer is used to deliver a series of short tones of varying frequency to the ear, either through a pair of headphones or via a sound transducer applied directly to the skull. The intensity of the sound is gradually reduced until it is no longer heard and this represents the threshold of hearing, at that frequency, through air and bone respectively. It may be necessary to play a masking noise into the opposite ear to prevent that ear from hearing the tones, enabling each ear to be tested independently.

General symptoms The following are some of the chief symptoms of ear disease: DEAFNESS (see DEAFNESS). EARACHE is most commonly due to acute in?ammation of the middle ear. Perceived pain in this region may be referred from other areas, such as the earache commonly experienced after tonsillectomy (removal of the TONSILS) or that caused by carious teeth (see TEETH, DISORDERS OF). The treatment will depend on the underlying cause. TINNITUS or ringing in the ear often accompanies deafness, but is sometimes the only symptom of ear disease. Even normal people sometimes experience tinnitus, particularly if put in soundproofed surroundings. It may be described as hissing, buzzing, the sound of the sea, or of bells. The intensity of the tinnitis usually ?uctuates, sometimes disappearing altogether. It may occur in almost any form of ear disease, but is particularly troublesome in nerve deafness due to ageing and in noise-induced deafness. The symptom seems to originate in the brain’s subcortical regions, high in the central nervous system. It may be a symptom of general diseases such as ANAEMIA, high blood pressure and arterial disease, in which cases it is often synchronous with the pulse, and may also be caused by drugs such as QUININE, salicylates (SALICYLIC ACID and its salts, for example, ASPIRIN) and certain ANTIBIOTICS. Treatment of any underlying ear disorder or systemic disease, including DEPRESSION, may reduce or even cure the tinnitis, but unfortunately in many cases the noises persist. Management involves psychological techniques and initially an explanation of the mechanism and reassurance that tinnitus does not signify brain disease, or an impending STROKE, may help the person. Tinnitus maskers – which look like hearing aids – have long been used with a suitably pitched sound helping to ‘mask’ the condition.

Diseases of the external ear

WAX (cerumen) is produced by specialised glands in the outer part of the ear canal only. Impacted wax within the ear canal can cause deafness, tinnitis and sometimes disturbance of balance. Wax can sometimes be softened with olive oil, 5-per-cent bicarbonate of soda or commercially prepared drops, and it will gradually liquefy and ‘remove itself’. If this is ineffective, syringing by a doctor or nurse will usually remove the wax but sometimes it is necessary for a specialist (otologist) to remove it manually with instruments. Syringing should not be done if perforation of the tympanic membrane (eardrum) is suspected. FOREIGN BODIES such as peas, beads or buttons may be found in the external ear canal, especially in children who have usually introduced them themselves. Live insects may also be trapped in the external canal causing intense irritation and noise, and in such cases spirit drops are ?rst instilled into the ear to kill the insect. Except in foreign bodies of vegetable origin, where swelling and pain may occur, syringing may be used to remove some foreign bodies, but often removal by a specialist using suitable instrumentation and an operating microscope is required. In children, a general anaesthetic may be needed. ACUTE OTITIS EXTERNA may be a di?use in?ammation or a boil (furuncle) occurring in the outer ear canal. The pinna is usually tender on movement (unlike acute otitis media – see below) and a discharge may be present. Initially treatment should be local, using magnesium sulphate paste or glycerine and 10-per-cent ichthaminol. Topical antibiotic drops can be used and sometimes antibiotics by mouth are necessary, especially if infection is acute. Clotrimazole drops are a useful antifungal treatment. Analgesics and locally applied warmth should relieve the pain.

CHRONIC OTITIS EXTERNA producing pain and discharge, can be caused by eczema, seborrhoeic DERMATITIS or PSORIASIS. Hair lotions and cosmetic preparations may trigger local allergic reactions in the external ear, and the chronic disorder may be the result of swimming or use of dirty towels. Careful cleaning of the ear by an ENT (Ear, Nose & Throat) surgeon and topical antibiotic or antifungal agents – along with removal of any precipitating cause – are the usual treatments. TUMOURS of the ear can arise in the skin of the auricle, often as a result of exposure to sunlight, and can be benign or malignant. Within the ear canal itself, the commonest tumours are benign outgrowths from the surrounding bone, said to occur in swimmers as a result of repeated exposure to cold water. Polyps may result from chronic infection of the ear canal and drum, particularly in the presence of a perforation. These polyps are soft and may be large enough to ?ll the ear canal, but may shrink considerably after treatment of the associated infection.

Diseases of the middle ear

OTITIS MEDIA or infection of the middle ear, usually occurs as a result of infection spreading up the Eustachian tubes from the nose, throat or sinuses. It may follow a cold, tonsillitis or sinusitis, and may also be caused by swimming and diving where water and infected secretions are forced up the Eustachian tube into the middle ear. Primarily it is a disease of children, with as many as 1.5 million cases occurring in Britain every year. Pain may be intense and throbbing or sharp in character. The condition is accompanied by deafness, fever and often TINNITUS.

In infants, crying may be the only sign that something is wrong – though this is usually accompanied by some localising manifestation such as rubbing or pulling at the ear. Examination of the ear usually reveals redness, and sometimes bulging, of the ear drum. In the early stages there is no discharge, but in the later stages there may be a discharge from perforation of the ear drum as a result of the pressure created in the middle ear by the accumulated pus. This is usually accompanied by an immediate reduction in pain.

Treatment consists of the immediate administration of an antibiotic, usually one of the penicillins (e.g. amoxicillin). In the majority of cases no further treatment is required, but if this does not quickly bring relief then it may be necessary to perform a myringotomy, or incision of the ear drum, to drain pus from the middle ear. When otitis media is treated immediately with su?cient dosage of the appropriate antibiotic, the chances of any permanent damage to the ear or to hearing are reduced to a negligible degree, as is the risk of any complications such as mastoiditis (discussed later in this section). CHRONIC OTITIS MEDIA WITH EFFUSION or glue ear, is the most common in?ammatory condition of the middle ear in children, to the extent that one in four children in the UK entering school has had an episode of ‘glue ear’. It is characterised by a persistent sticky ?uid in the middle ear (hence the name); this causes a conductive-type deafness. It may be associated with enlarged adenoids (see NOSE, DISORDERS OF) which impair the function of the Eustachian tube. If the hearing impairment is persistent and causes problems, drainage of the ?uid, along with antibiotic treatment, may be needed – possibly in conjunction with removal of the adenoids. The insertion of grommets (ventilation tubes) was for a time standard treatment, but while hearing is often restored, there may be no long-term gain and even a risk of damage to the tympanic membrane, so the operation is less popular than it was a decade or so ago. MASTOIDITIS is a serious complication of in?ammation of the middle ear, the incidence of which has been dramatically reduced by the introduction of antibiotics. In?ammation in this cavity usually arises by direct spread of acute or chronic in?ammation from the middle ear. The signs of this condition include swelling and tenderness of the skin behind the ear, redness and swelling inside the ear, pain in the side of the head, high fever, and a discharge from the ear. The management of this condition in the ?rst instance is with antibiotics, usually given intravenously; however, if the condition fails to improve, surgical treatment is necessary. This involves draining any pus from the middle ear and mastoid, and removing diseased lining and bone from the mastoid.

Diseases of the inner ear

MENIÈRE’S DISEASE is a common idiopathic disorder of ENDOLYMPH control in the semicircular canals (see EAR), characterised by the triad of episodic VERTIGO with deafness and tinnitus. The cause is unknown and usually one ear only is affected at ?rst, but eventually the opposite ear is affected in approximately 50 per cent of cases. The onset of dizziness is often sudden and lasts for up to 24 hours. The hearing loss is temporary in the early stages, but with each attack there may be a progressive nerve deafness. Nausea and vomiting often occur. Treatment during the attacks includes rest and drugs to control sickness. Vasodilator drugs such as betahistine hydrochloride may be helpful. Surgical treatment is sometimes required if crippling attacks of dizziness persist despite these measures. OTOSCLEROSIS A disorder of the middle ear that results in progressive deafness. Often running in families, otosclerosis affects about one person in 200; it customarily occurs early in adult life. An overgrowth of bone ?xes the stapes (the innermost bone of the middle ear) and stops sound vibrations from being transmitted to the inner ear. The result is conductive deafness. The disorder usually affects both ears. Those affected tend to talk quietly and deafness increases over a 10–15 year period. Tinnitus often occurs, and occasionally vertigo.

Abnormal hearing tests point to the diagnosis; the deafness may be partially overcome with a hearing aid but surgery is eventually needed. This involves replacing the stapes bone with a synthetic substitute (stapedectomy). (See also OTIC BAROTRAUMA.)... ear, diseases of

Functional Diseases

See PSYCHOSOMATIC DISEASES.... functional diseases

Gums, Diseases Of

See MOUTH, DISEASES OF; TEETH, DISEASES OF.... gums, diseases of

Heart, Diseases Of

Heart disease can affect any of the structures of the HEART and may affect more than one at a time. Heart attack is an imprecise term and may refer to ANGINA PECTORIS (a symptom of pain originating in the heart) or to coronary artery thrombosis, also called myocardial infarction.

Arrhythmias An abnormal rate or rhythm of the heartbeat. The reason is a disturbance in the electrical impulses within the heart. Sometimes a person may have an occasional irregular heartbeat: this is called an ECTOPIC beat (or an extrasystole) and does not necessarily mean that an abnormality exists. There are two main types of arrhythmia: bradycardias, where the rate is slow – fewer than 60 beats a minute and sometimes so slow and unpredictable (heartblock) as to cause blackouts or heart failure; and tachycardia, where the rate is fast – more than 100 beats a minute. A common cause of arrhythmia is coronary artery disease, when vessels carrying blood to the heart are narrowed by fatty deposits (ATHEROMA), thus reducing the blood supply and damaging the heart tissue. This condition often causes myocardial infarction after which arrhythmias are quite common and may need correcting by DEFIBRILLATION (application of a short electric shock to the heart). Some tachycardias result from a defect in the electrical conduction system of the heart that is commonly congenital. Various drugs can be used to treat arrhythmias (see ANTIARRHYTHMIC DRUGS). If attacks constantly recur, the arrhythmia may be corrected by electrical removal of dead or diseased tissue that is the cause of the disorder. Heartblock is most e?ectively treated with an arti?cial CARDIAC PACEMAKER, a battery-activated control unit implanted in the chest.

Cardiomyopathy Any disease of the heart muscle that results in weakening of its contractions. The consequence is a fall in the e?ciency of the circulation of blood through the lungs and remainder of the body structures. The myopathy may be due to infection, disordered metabolism, nutritional excess or de?ciency, toxic agents, autoimmune processes, degeneration, or inheritance. Often, however, the cause is not identi?ed. Cardiomyopathies are less common than other types of heart diseases, and the incidence of di?erent types of myopathy (see below) is not known because patients or doctors are sometimes unaware of the presence of the condition.

The three recognised groups of cardiomyopathies are hypertrophic, dilated and restrictive.

•Hypertrophic myopathy, a familial condition, is characterised by great enlargement of the muscle of the heart ventricles. This reduces the muscle’s e?ciency, the ventricles fail to relax properly and do not ?ll suf?ciently during DIASTOLE.

In the dilated type of cardiomyopathy, both ventricles overdilate, impairing the e?ciency of contraction and causing congestion of the lungs.

In the restrictive variety, proper ?lling of the ventricles does not occur because the muscle walls are less elastic than normal. The result is raised pressure in the two atria (upper cavities) of the heart: these dilate and develop FIBRILLATION. Diagnosis can be di?cult and treatment is symptomatic, with a poor prognosis. In suitable patients, heart TRANSPLANTATION may be considered. Disorders of the heart muscle may also be

caused by poisoning – for example, heavy consumption of alcohol. Symptoms include tiredness, palpitations (quicker and sometimes irregular heartbeat), chest pain, di?culty in breathing, and swelling of the legs and hands due to accumulation of ?uid (OEDEMA). The heart is enlarged (as shown on chest X-ray) and ECHOCARDIOGRAPHY shows thickening of the heart muscle. A BIOPSY of heart muscle will show abnormalities in the cells of the heart muscle.

Where the cause of cardiomyopathy is unknown, as is the case with most patients, treatment is symptomatic using DIURETICS to control heart failure and drugs such as DIGOXIN to return the heart rhythm to normal. Patients should stop drinking alcohol. If, as often happens, the patient’s condition slowly deteriorates, heart transplantation should be considered.

Congenital heart disease accounts for 1–2 per cent of all cases of organic heart disease. It may be genetically determined and so inherited; present at birth for no obvious reason; or, in rare cases, related to RUBELLA in the mother. The most common forms are holes in the heart (atrial septal defect, ventricular septal defect – see SEPTAL DEFECT), a patent DUCTUS ARTERIOSUS, and COARCTATION OF THE AORTA. Many complex forms also exist and can be diagnosed in the womb by fetal echocardiography which can lead to elective termination of pregnancy. Surgery to correct many of these abnormalities is feasible, even for the most severe abnormalities, but may only be palliative giving rise to major diffculties of management as the children become older. Heart transplantation is now increasingly employed for the uncorrectable lesions.

Coronary artery disease Also known as ischaemic heart disease, this is a common cause of symptoms and death in the adult population. It may present for the ?rst time as sudden death, but more usually causes ANGINA PECTORIS, myocardial infarction (heart attack) or heart failure. It can also lead to a disturbance of heart rhythm. Factors associated with an increased risk of developing coronary artery disease include diabetes, cigarette smoking, high blood pressure, obesity, and a raised concentration of cholesterol in the blood. Older males are most affected.

Coronary thrombosis or acute myocardial infarction is the acute, dramatic manifestation of coronary-artery ischaemic heart disease – one of the major killing diseases of western civilisation. In 1999, ischaemic heart disease was responsible for about 115,000 deaths in England and Wales, compared with 153,000 deaths in 1988. In 1999 more than 55,600 people died of coronary thrombosis. The underlying cause is disease of the coronary arteries which carry the blood supply to the heart muscle (or myocardium). This results in narrowing of the arteries until ?nally they are unable to transport su?cient blood for the myocardium to function e?ciently. One of three things may happen. If the narrowing of the coronary arteries occurs gradually, then the individual concerned will develop either angina pectoris or signs of a failing heart: irregular rhythm, breathlessness, CYANOSIS and oedema.

If the narrowing occurs suddenly or leads to complete blockage (occlusion) of a major branch of one of the coronary arteries, then the victim collapses with acute pain and distress. This is the condition commonly referred to as a coronary thrombosis because it is usually due to the affected artery suddenly becoming completely blocked by THROMBOSIS. More correctly, it should be described as coronary occlusion, because the ?nal occluding factor need not necessarily be thrombosis.

Causes The precise cause is not known, but a wide range of factors play a part in inducing coronary artery disease. Heredity is an important factor. The condition is more common in men than in women; it is also more common in those in sedentary occupations than in those who lead a more physically active life, and more likely to occur in those with high blood pressure than in those with normal blood pressure (see HYPERTENSION). Obesity is a contributory factor. The disease is more common among smokers than non-smokers; it is also often associated with a high level of CHOLESTEROL in the blood, which in turn has been linked with an excessive consumption of animal, as opposed to vegetable, fats. In this connection the important factors seem to be the saturated fatty acids (low-density and very low-density lipoproteins [LDLs and VLDLs] – see CHOLESTEROL) of animal fats which would appear to be more likely to lead to a high level of cholesterol in the blood than the unsaturated fatty acids of vegetable fats. As more research on the subject is carried out, the arguments continue about the relative in?uence of the di?erent factors. (For advice on prevention of the disease, see APPENDIX 2: ADDRESSES: SOURCES OF INFORMATION, ADVICE, SUPPORT AND SELFHELP.)

Symptoms The presenting symptom is the sudden onset, often at rest, of acute, agonising pain in the front of the chest. This rapidly radiates all over the front of the chest and often down over the abdomen. The pain is frequently accompanied by nausea and vomiting, so that suspicion may be aroused of some acute abdominal condition such as biliary colic (see GALLBLADDER, DISEASES OF) or a perforated PEPTIC ULCER. The victim soon goes into SHOCK, with a pale, cold, sweating skin, rapid pulse and dif?culty in breathing. There is usually some rise in temperature.

Treatment is immediate relief of the pain by injections of diamorphine. Thrombolytic drugs should be given as soon as possible (‘rapid door to needle time’) and ARRHYTHMIA corrected. OXYGEN is essential and oral ASPIRIN is valuable. Treatment within the ?rst hour makes a great di?erence to recovery. Subsequent treatment includes the continued administration of drugs to relieve the pain; the administration of ANTIARRHYTHMIC DRUGS that may be necessary to deal with the heart failure that commonly develops, and the irregular action of the heart that quite often develops; and the continued administration of oxygen. Patients are usually admitted to coronary care units, where they receive constant supervision. Such units maintain an emergency, skilled, round-the-clock sta? of doctors and nurses, as well as all the necessary resuscitation facilities that may be required.

The outcome varies considerably. The ?rst (golden) hour is when the patient is at greatest risk of death: if he or she is treated, then there is a 50 per cent reduction in mortality compared with waiting until hospital admission. As each day passes the prognosis improves with a ?rst coronary thrombosis, provided that the patient does not have a high blood pressure and is not overweight. Following recovery, there should be a gradual return to work, care being taken to avoid any increase in weight, unnecessary stress and strain, and to observe moderation in all things. Smoking must stop. In uncomplicated cases patients get up and about as soon as possible, most being in hospital for a week to ten days and back at work in three months or sooner.

Valvular heart disease primarily affects the mitral and aortic valves which can become narrowed (stenosis) or leaking (incompetence). Pulmonary valve problems are usually congenital (stenosis) and the tricuspid valve is sometimes involved when rheumatic heart disease primarily affects the mitral or aortic valves. RHEUMATIC FEVER, usually in childhood, remains a common cause of chronic valvular heart disease causing stenosis, incompetence or both of the aortic and mitral valves, but each valve has other separate causes for malfunction.

Aortic valve disease is more common with increasing age. When the valve is narrowed, the heart hypertrophies and may later fail. Symptoms of angina or breathlessness are common and dizziness or blackouts (syncope) also occur. Replacing the valve is a very e?ective treatment, even with advancing age. Aortic stenosis may be caused by degeneration (senile calci?c), by the inheritance of two valvular leaflets instead of the usual three (bicuspid valve), or by rheumatic fever. Aortic incompetence again leads to hypertrophy, but dilatation is more common as blood leaks back into the ventricle. Breathlessness is the more common complaint. The causes are the same as stenosis but also include in?ammatory conditions such as SYPHILIS or ANKYLOSING SPONDYLITIS and other disorders of connective tissue. The valve may also leak if the aorta dilates, stretching the valve ring as with HYPERTENSION, aortic ANEURYSM and MARFAN’S SYNDROME – an inherited disorder of connective tissue that causes heart defects. Infection (endocarditis) can worsen acutely or chronically destroy the valve and sometimes lead to abnormal outgrowths on the valve (vegetations) which may break free and cause devastating damage such as a stroke or blocked circulation to the bowel or leg.

Mitral valve disease leading to stenosis is rheumatic in origin. Mitral incompetence may be rheumatic but in the absence of stenosis can be due to ISCHAEMIA, INFARCTION, in?ammation, infection and a congenital weakness (prolapse). The valve may also leak if stretched by a dilating ventricle (functional incompetence). Infection (endocarditis) may affect the valve in a similar way to aortic disease. Mitral symptoms are predominantly breathlessness which may lead to wheezing or waking at night breathless and needing to sit up or stand for relief. They are made worse when the heart rhythm changes (atrial ?brillation) which is frequent as the disease becomes more severe. This leads to a loss of e?ciency of up to 25 per cent and a predisposition to clot formation as blood stagnates rather than leaves the heart e?ciently. Mitral incompetence may remain mild and be of no trouble for many years, but infection must be guarded against (endocarditis prophylaxis).

Endocarditis is an infection of the heart which may acutely destroy a valve or may lead to chronic destruction. Bacteria settle usually on a mild lesion. Antibiotics taken at vulnerable times can prevent this (antibiotic prophylaxis) – for example, before tooth extraction. If established, lengthy intravenous antibiotic therapy is needed and surgery is often necessary. The mortality is 30 per cent but may be higher if the infection settles on a replaced valve (prosthetic endocarditis). Complications include heart failure, shock, embolisation (generation of small clots in the blood), and cerebral (mental) confusion.

PERICARDITIS is an in?ammation of the sac covering the outside of the heart. The sac becomes roughened and pain occurs as the heart and sac rub together. This is heard by stethoscope as a scratching noise (pericardial rub). Fever is often present and a virus the main cause. It may also occur with rheumatic fever, kidney failure, TUBERCULOSIS or from an adjacent lung problem such as PNEUMONIA or cancer. The in?ammation may cause ?uid to accumulate between the sac and the heart (e?usion) which may compress the heart causing a fall in blood pressure, a weak pulse and circulatory failure (tamponade). This can be relieved by aspirating the ?uid. The treatment is then directed at the underlying cause.... heart, diseases of

Industrial Diseases

See OCCUPATIONAL HEALTH, MEDICINE AND DISEASES.... industrial diseases

International Statistical Classification Of Diseases And Related Health Problems, Tenth Revision (icd-10)

A list of diagnoses and identifying codes used by medical practitioners and other health care providers. The coding and terminology provide a uniform language that permits consistent communication on claim forms. Data from earlier time periods were coded using the appropriate revision of the ICD for that time period. Changes in classification of causes of death in successive revisions of the ICD may introduce discontinuities in cause of death statistics over time.... international statistical classification of diseases and related health problems, tenth revision (icd-10)

Nails, Diseases Of

Disease may affect the nail fold, nail plate or nail bed (see SKIN – Nail). In?ammation of the nail fold is called paronychia: acute paronychia is usually caused by a minor injury allowing in bacteria, which set up infection; chronic paronychia is often an occupational hazard, due to constant exposure of the hands to water – for example, in the catering industry, agriculture and housework – but may also be caused by impaired circulation in the ?ngers. Often, ANTIBIOTICS are su?cient for treatment, but sometimes surgical incision is needed.

PSORIASIS is a common cause of disease of the nail plate, as are eczema (see DERMATITIS) and fungal infection (see FUNGAL AND YEAST INFECTIONS). Deformity of the nail may point to systemic disease, as in CLUBBING, or the spoon-shaped concave nails (koilonychia) of severe iron de?ciency. Acute toxic illnesses may temporarily disturb nail growth causing horizontal ridges (Beau’s lines) which grow out slowly.

Onycholysis is separation of the nail plate from its bed. It may be due to psoriasis of the nail bed and trauma, or may occur spontaneously. Gross thickening of nails is common in the toes, caused by psoriasis or fungal infection.... nails, diseases of

Nipples, Diseases Of

See BREASTS, DISEASES OF.... nipples, diseases of

Occupational Health, Medicine And Diseases

Occupational health The e?ect of work on human health, and the impact of workers’ health on their work. Although the term encompasses the identi?cation and treatment of speci?c occupational diseases, occupational health is also an applied and multidisciplinary subject concerned with the prevention of occupational ill-health caused by chemical, biological, physical and psychosocial factors, and the promotion of a healthy and productive workforce.

Occupational health includes both mental and physical health. It is about compliance with health-and-safety-at-work legislation (and common law duties) and about best practice in providing work environments that reduce risks to health and safety to lowest practicable levels. It includes workers’ ?tness to work, as well as the management of the work environment to accommodate people with disabilities, and procedures to facilitate the return to work of those absent with long-term illness. Occupational health incorporates several professional groups, including occupational physicians, occupational health nurses, occupational hygienists, ergonomists, disability managers, workplace counsellors, health-and-safety practitioners, and workplace physiotherapists.

In the UK, two key statutes provide a framework for occupational health: the Health and Safety at Work, etc. Act 1974 (HSW Act); and the Disability Discrimination Act 1995 (DDA). The HSW Act states that employers have a duty to protect the health, safety and welfare of their employees and to conduct their business in a way that does not expose others to risks to their health and safety. Employees and self-employed people also have duties under the Act. Modern health-and-safety legislation focuses on assessing and controlling risk rather than prescribing speci?c actions in di?erent industrial settings. Various regulations made under the HSW Act, such as the Control of Substances Hazardous to Health Regulations, the Manual Handling Operations Regulations and the Noise at Work Regulations, set out duties with regard to di?erent risks, but apply to all employers and follow the general principles of risk assessment and control. Risks should be controlled principally by removing or reducing the hazard at source (for example, by substituting chemicals with safer alternatives, replacing noisy machinery, or automating tasks to avoid heavy lifting). Personal protective equipment, such as gloves and ear defenders, should be seen as a last line of defence after other control measures have been put in place.

The employment provisions of the DDA require employers to avoid discriminatory practice towards disabled people and to make reasonable adjustments to working arrangements where a disabled person is placed at a substantial disadvantage to a non-disabled person. Although the DDA does not require employers to provide access to rehabilitation services – even for those injured or made ill at work – occupational-health practitioners may become involved in programmes to help people get back to work after injury or long-term illness, and many businesses see the retention of valuable sta? as an attractive alternative to medical retirement or dismissal on health grounds.

Although a major part of occupational-health practice is concerned with statutory compliance, the workplace is also an important venue for health promotion. Many working people rarely see their general practitioner and, even when they do, there is little time to discuss wider health issues. Occupational-health advisers can ?ll in this gap by providing, for example, workplace initiatives on stopping smoking, cardiovascular health, diet and self-examination for breast and testicular cancers. Such initiatives are encouraged because of the perceived bene?ts to sta?, to the employing organisation and to the wider public-health agenda. Occupational psychologists recognise the need for the working population to achieve a ‘work-life balance’ and the promotion of this is an increasing part of occupational health strategies.

The law requires employers to consult with their sta? on health-and-safety matters. However, there is also a growing understanding that successful occupational-health management involves workers directly in the identi?cation of risks and in developing solutions in the workplace. Trade unions play an active role in promoting occupational health through local and national campaigns and by training and advising elected workplace safety representatives.

Occupational medicine The branch of medicine that deals with the control, prevention, diagnosis, treatment and management of ill-health and injuries caused or made worse by work, and with ensuring that workers are ?t for the work they do.

Occupational medicine includes: statutory surveillance of workers’ exposure to hazardous agents; advice to employers and employees on eliminating or reducing risks to health and safety at work; diagnosis and treatment/management of occupational illness; advice on adapting the working environment to suit the worker, particularly those with disabilities or long-term health problems; and advice on the return to work and, if necessary, rehabilitation of workers absent through illness. Occupational physicians may play a wider role in monitoring the health of workplace populations and in advising employers on controlling health hazards where ill-health trends are observed. They may also conduct epidemiological research (see EPIDEMIOLOGY) on workplace diseases.

Because of the occupational physician’s dual role as adviser to both employer and employee, he or she is required to be particularly diligent with regards to the individual worker’s medical CONFIDENTIALITY. Occupational physicians need to recognise in any given situation the context they are working in, and to make sure that all parties are aware of this.

Occupational medicine is a medical discipline and thus is only part of the broader ?eld of occupational health. Although there are some speci?c clinical duties associated with occupational medicine, such as diagnosis of occupational disease and medical screening, occupational physicians are frequently part of a multidisciplinary team that might include, for example, occupational-health nurses, healthand-safety advisers, ergonomists, counsellors and hygienists. Occupational physicians are medical practitioners with a post-registration quali?cation in occupational medicine. They will have completed a period of supervised in-post training. In the UK, the Faculty of Occupational Medicine of the Royal College of Physicians has three categories of membership, depending on quali?cations and experience: associateship (AFOM); membership (MFOM); and fellowship (FFOM).

Occupational diseases Occupational diseases are illnesses that are caused or made worse by work. In their widest sense, they include physical and mental ill-health conditions.

In diagnosing an occupational disease, the clinician will need to examine not just the signs and symptoms of ill-health, but also the occupational history of the patient. This is important not only in discovering the cause, or causes, of the disease (work may be one of a number of factors), but also in making recommendations on how the work should be modi?ed to prevent a recurrence – or, if necessary, in deciding whether or not the worker is able to return to that type of work. The occupational history will help in deciding whether or not other workers are also at risk of developing the condition. It will include information on:

the nature of the work.

how the tasks are performed in practice.

the likelihood of exposure to hazardous agents (physical, chemical, biological and psychosocial).

what control measures are in place and the extent to which these are adhered to.

previous occupational and non-occupational exposures.

whether or not others have reported similar symptoms in relation to the work. Some conditions – certain skin conditions,

for example – may show a close relationship to work, with symptoms appearing directly only after exposure to particular agents or possibly disappearing at weekends or with time away from work. Others, however, may be chronic and can have serious long-term implications for a person’s future health and employment.

Statistical information on the prevalence of occupational disease in the UK comes from a variety of sources, including o?cial ?gures from the Industrial Injuries Scheme (see below) and statutory reporting of occupational disease (also below). Neither of these o?cial schemes provides a representative picture, because the former is restricted to certain prescribed conditions and occupations, and the latter suffers from gross under-reporting. More useful are data from the various schemes that make up the Occupational Diseases Intelligence Network (ODIN) and from the Labour Force Survey (LFS). ODIN data is generated by the systematic reporting of work-related conditions by clinicians and includes several schemes. Under one scheme, more than 80 per cent of all reported diseases by occupational-health physicians fall into just six of the 42 clinical disease categories: upper-limb disorders; anxiety, depression and stress disorders; contact DERMATITIS; lower-back problems; hearing loss (see DEAFNESS); and ASTHMA. Information from the LFS yields a similar pattern in terms of disease frequency. Its most recent survey found that over 2 million people believed that, in the previous 12 months, they had suffered from an illness caused or made worse by work and that

19.5 million working days were lost as a result. The ten most frequently reported disease categories were:

stress and mental ill-health (see MENTAL ILLNESS): 515,000 cases.

back injuries: 508,000.

upper-limb and neck disorders: 375,000.

lower respiratory disease: 202,000.

deafness, TINNITUS or other ear conditions: 170,000.

lower-limb musculoskeletal conditions: 100,000.

skin disease: 66,000.

headache or ‘eyestrain’: 50,000.

traumatic injury (includes wounds and fractures from violent attacks at work): 34,000.

vibration white ?nger (hand-arm vibration syndrome): 36,000. A person who develops a chronic occu

pational disease may be able to sue his or her employer for damages if it can be shown that the employer was negligent in failing to take reasonable care of its employees, or had failed to provide a system of work that would have prevented harmful exposure to a known health hazard. There have been numerous successful claims (either awarded in court, or settled out of court) for damages for back and other musculoskeletal injuries, hand-arm vibration syndrome, noise-induced deafness, asthma, dermatitis, MESOTHELIOMA and ASBESTOSIS. Employers’ liability (workers’ compensation) insurers are predicting that the biggest future rise in damages claims will be for stress-related illness. In a recent study, funded by the Health and Safety Executive, about 20 per cent of all workers – more than 5 million people in the UK – claimed to be ‘very’ or ‘extremely’ stressed at work – a statistic that is likely to have a major impact on the long-term health of the working population.

While victims of occupational disease have the right to sue their employers for damages, many countries also operate a system of no-fault compensation for the victims of prescribed occupational diseases. In the UK, more than 60 diseases are prescribed under the Industrial Injuries Scheme and a person will automatically be entitled to state compensation for disability connected to one of these conditions, provided that he or she works in one of the occupations for which they are prescribed. The following short list gives an indication of the types of diseases and occupations prescribed under the scheme:

CARPAL TUNNEL SYNDROME connected to the use of hand-held vibrating tools.

hearing loss from (amongst others) use of pneumatic percussive tools and chainsaws, working in the vicinity of textile manufacturing or woodworking machines, and work in ships’ engine rooms.

LEPTOSPIROSIS – infection with Leptospira (various listed occupations).

viral HEPATITIS from contact with human blood, blood products or other sources of viral hepatitis.

LEAD POISONING, from any occupation causing exposure to fumes, dust and vapour from lead or lead products.

asthma caused by exposure to, among other listed substances, isocyanates, curing agents, solder ?ux fumes and insects reared for research.

mesothelioma from exposure to asbestos.

In the UK, employers and the self-employed have a duty to report all occupational injuries (if the employee is o? work for three days or more as a result), diseases or dangerous incidents to the relevant enforcing authority (the Health and Safety Executive or local-authority environmental-health department) under the Reporting of Injuries, Diseases and Dangerous Occurrences Regulations 1995 (RIDDOR). Despite this statutory duty, comparatively few diseases are reported so that ?gures generated from RIDDOR reports do not give a useful indication of the scale of occupational diseases in the UK. The statutory reporting of injuries is much better, presumably because of the clear and acute relationship between a workplace accident and the resultant injury. More than 160,000 injuries are reported under RIDDOR every year compared with just 2,500 or so occupational diseases, a gross underestimate of the true ?gure.

There are no precise ?gures for the number of people who die prematurely because of work-related ill-health, and it would be impossible to gauge the exact contribution that work has on, for example, cardiovascular disease and cancers where the causes are multifactorial. The toll would, however, dwarf the number of deaths caused by accidents at work. Around 250 people are killed by accidents at work in the UK each year – mesothelioma, from exposure to asbestos at work, alone kills more than 1,300 people annually.

The following is a sample list of occupational diseases, with brief descriptions of their aetiologies.

Inhaled materials

PNEUMOCONIOSIS covers a group of diseases which cause ?brotic lung disease following the inhalation of dust. Around 250–300 new cases receive bene?t each year – mostly due to coal dust with or without silica contamination. SILICOSIS is the more severe disease. The contraction in the size of the coal-mining industry as well as improved dust suppression in the mines have diminished the importance of this disease, whereas asbestos-related diseases now exceed 1,000 per year. Asbestos ?bres cause a restrictive lung disease but also are responsible for certain malignant conditions such as pleural and peritoneal mesothelioma and lung cancer. The lung-cancer risk is exacerbated by cigarette-smoking.

Even though the use of asbestos is virtually banned in the UK, many workers remain at risk of exposure because of the vast quantities present in buildings (much of which is not listed in building plans). Carpenters, electricians, plumbers, builders and demolition workers are all liable to exposure from work that disturbs existing asbestos. OCCUPATIONAL ASTHMA is of increasing importance – not only because of the recognition of new allergic agents (see ALLERGY), but also in the number of reported cases. The following eight substances are most frequently linked to occupational asthma (key occupations in brackets): isocyanates (spray painters, electrical processors); ?our and grain (bakers and farmers); wood dust (wood workers); glutaraldehyde (nurses, darkroom technicians); solder/colophony (welders, electronic assembly workers); laboratory animals (technicians, scientists); resins and glues (metal and electrical workers, construction, chemical processors); and latex (nurses, auxiliaries, laboratory technicians).

The disease develops after a short, symptomless period of exposure; symptoms are temporally related to work exposures and relieved by absences from work. Removal of the worker from exposure does not necessarily lead to complete cessation of symptoms. For many agents, there is no relationship with a previous history of ATOPY. Occupational asthma accounts for about 10 per cent of all asthma cases. DERMATITIS The risk of dermatitis caused by an allergic or irritant reaction to substances used or handled at work is present in a wide variety of jobs. About three-quarters of cases are irritant contact dermatitis due to such agents as acids, alkalis and solvents. Allergic contact dermatitis is a more speci?c response by susceptible individuals to a range of allergens (see ALLERGEN). The main occupational contact allergens include chromates, nickel, epoxy resins, rubber additives, germicidal agents, dyes, topical anaesthetics and antibiotics as well as certain plants and woods. Latex gloves are a particular cause of occupational dermatitis among health-care and laboratory sta? and have resulted in many workers being forced to leave their profession through ill-health. (See also SKIN, DISEASES OF.)

Musculoskeletal disorders Musculoskeletal injuries are by far the most common conditions related to work (see LFS ?gures, above) and the biggest cause of disability. Although not all work-related, musculoskeletal disorders account for 36.5 per cent of all disabilities among working-age people (compared with less than 4 per cent for sight and hearing impairment). Back pain (all causes – see BACKACHE) has been estimated to cause more than 50 million days lost every year in sickness absence and costs the UK economy up to £5 billion annually as a result of incapacity or disability. Back pain is a particular problem in the health-care sector because of the risk of injury from lifting and moving patients. While the emphasis should be on preventing injuries from occurring, it is now well established that the best way to manage most lower-back injuries is to encourage the patient to continue as normally as possible and to remain at work, or to return as soon as possible even if the patient has some residual back pain. Those who remain o? work on long-term sick leave are far less likely ever to return to work.

Aside from back injuries, there are a whole range of conditions affecting the upper limbs, neck and lower limbs. Some have clear aetiologies and clinical signs, while others are less well de?ned and have multiple causation. Some conditions, such as carpal tunnel syndrome, are prescribed diseases in certain occupations; however, they are not always caused by work (pregnant and older women are more likely to report carpal tunnel syndrome irrespective of work) and clinicians need to be careful when assigning work as the cause without ?rst considering the evidence. Other conditions may be revealed or made worse by work – such as OSTEOARTHRITIS in the hand. Much attention has focused on injuries caused by repeated movement, excessive force, and awkward postures and these include tenosynovitis (in?ammation of a tendon) and epicondylitis. The greatest controversy surrounds upper-limb disorders that do not present obvious tissue or nerve damage but nevertheless give signi?cant pain and discomfort to the individual. These are sometimes referred to as ‘repetitive strain injury’ or ‘di?use RSI’. The diagnosis of such conditions is controversial, making it di?cult for sufferers to pursue claims for compensation through the courts. Psychosocial factors, such as high demands of the job, lack of control and poor social support at work, have been implicated in the development of many upper-limb disorders, and in prevention and management it is important to deal with the psychological as well as the physical risk factors. Occupations known to be at particular risk of work-related upper-limb disorders include poultry processors, packers, electronic assembly workers, data processors, supermarket check-out operators and telephonists. These jobs often contain a number of the relevant exposures of dynamic load, static load, a full or excessive range of movements and awkward postures. (See UPPER LIMB DISORDERS.)

Physical agents A number of physical agents cause occupational ill-health of which the most important is occupational deafness. Workplace noise exposures in excess of 85 decibels for a working day are likely to cause damage to hearing which is initially restricted to the vital frequencies associated with speech – around 3–4 kHz. Protection from such noise is imperative as hearing aids do nothing to ameliorate the neural damage once it has occurred.

Hand-arm vibration syndrome is a disorder of the vascular and/or neural endings in the hands leading to episodic blanching (‘white ?nger’) and numbness which is exacerbated by low temperature. The condition, which is caused by vibrating tools such as chain saws and pneumatic hammers, is akin to RAYNAUD’S DISEASE and can be disabling.

Decompression sickness is caused by a rapid change in ambient pressure and is a disease associated with deep-sea divers, tunnel workers and high-?ying aviators. Apart from the direct effects of pressure change such as ruptured tympanic membrane or sinus pain, the more serious damage is indirectly due to nitrogen bubbles appearing in the blood and blocking small vessels. Central and peripheral nervous-system damage and bone necrosis are the most dangerous sequelae.

Radiation Non-ionising radiation from lasers or microwaves can cause severe localised heating leading to tissue damage of which cataracts (see under EYE, DISORDERS OF) are a particular variety. Ionising radiation from radioactive sources can cause similar acute tissue damage to the eyes as well as cell damage to rapidly dividing cells in the gut and bone marrow. Longer-term effects include genetic damage and various malignant disorders of which LEUKAEMIA and aplastic ANAEMIA are notable. Particular radioactive isotopes may destroy or induce malignant change in target organs, for example, 131I (thyroid), 90Sr (bone). Outdoor workers may also be at risk of sunburn and skin cancers. OTHER OCCUPATIONAL CANCERS Occupation is directly responsible for about 5 per cent of all cancers and contributes to a further 5 per cent. Apart from the cancers caused by asbestos and ionising radiation, a number of other occupational exposures can cause human cancer. The International Agency for Research on Cancer regularly reviews the evidence for carcinogenicity of compounds and industrial processes, and its published list of carcinogens is widely accepted as the current state of knowledge. More than 50 agents and processes are listed as class 1 carcinogens. Important occupational carcinogens include asbestos (mesothelioma, lung cancer); polynuclear aromatic hydrocarbons such as mineral oils, soots, tars (skin and lung cancer); the aromatic amines in dyestu?s (bladder cancer); certain hexavalent chromates, arsenic and nickel re?ning (lung cancer); wood and leather dust (nasal sinus cancer); benzene (leukaemia); and vinyl chloride monomer (angiosarcoma of the liver). It has been estimated that elimination of all known occupational carcinogens, if possible, would lead to an annual saving of 5,000 premature deaths in Britain.

Infections Two broad categories of job carry an occupational risk. These are workers in contact with animals (farmers, veterinary surgeons and slaughtermen) and those in contact with human sources of infection (health-care sta? and sewage workers).

Occupational infections include various zoonoses (pathogens transmissible from animals to humans), such as ANTHRAX, Borrelia burgdorferi (LYME DISEASE), bovine TUBERCULOSIS, BRUCELLOSIS, Chlamydia psittaci, leptospirosis, ORF virus, Q fever, RINGWORM and Streptococcus suis. Human pathogens that may be transmissible at work include tuberculosis, and blood-borne pathogens such as viral hepatitis (B and C) and HIV (see AIDS/HIV). Health-care workers at risk of exposure to infected blood and body ?uids should be immunised against hapatitis B.

Poisoning The incidence of occupational poisonings has diminished with the substitution of noxious chemicals with safer alternatives, and with the advent of improved containment. However, poisonings owing to accidents at work are still reported, sometimes with fatal consequences. Workers involved in the application of pesticides are particularly at risk if safe procedures are not followed or if equipment is faulty. Exposure to organophosphate pesticides, for example, can lead to breathing diffculties, vomiting, diarrhoea and abdominal cramps, and to other neurological effects including confusion and dizziness. Severe poisonings can lead to death. Exposure can be through ingestion, inhalation and dermal (skin) contact.

Stress and mental health Stress is an adverse reaction to excessive pressures or demands and, in occupational-health terms, is di?erent from the motivational impact often associated with challenging work (some refer to this as ‘positive stress’). Stress at work is often linked to increasing demands on workers, although coping can often prevent the development of stress. The causes of occupational stress are multivariate and encompass job characteristics (e.g. long or unsocial working hours, high work demands, imbalance between e?ort and reward, poorly managed organisational change, lack of control over work, poor social support at work, fear of redundancy and bullying), as well as individual factors (such as personality type, personal circumstances, coping strategies, and availability of psychosocial support outside work). Stress may in?uence behaviours such as smoking, alcohol consumption, sleep and diet, which may in turn affect people’s health. Stress may also have direct effects on the immune system (see IMMUNITY) and lead to a decline in health. Stress may also alter the course and response to treatment of conditions such as cardiovascular disease. As well as these general effects of stress, speci?c types of disorder may be observed.

Exposure to extremely traumatic incidents at work – such as dealing with a major accident involving multiple loss of life and serious injury

(e.g. paramedics at the scene of an explosion or rail crash) – may result in a chronic condition known as post-traumatic stress disorder (PTSD). PTSD is an abnormal psychological reaction to a traumatic event and is characterised by extreme psychological discomfort, such as anxiety or panic when reminded of the causative event; sufferers may be plagued with uncontrollable memories and can feel as if they are going through the trauma again. PTSD is a clinically de?ned condition in terms of its symptoms and causes and should not be used to include normal short-term reactions to trauma.... occupational health, medicine and diseases

Pulmonary Diseases

See LUNGS, DISEASES OF.... pulmonary diseases

Renal Diseases

See KIDNEYS, DISEASES OF.... renal diseases

Somatoform Diseases

A group of disorders in which the affected individuals suffer from repeated physical symptoms for which no physical cause can be discovered. Somatisation is the process by which a person’s psychological needs are expressed in the form of physical symptoms. (See also PSYCHOSOMATIC DISEASES.)... somatoform diseases

Stomach, Diseases Of

Gastritis is the description for several unrelated diseases of the gastric mucosa.

Acute gastritis is an in?ammatory reaction of the gastric mucosa to various precipitating factors, ranging from physical and chemical injury to infections. Acute gastritis (especially of the antral mucosas) may well represent a reaction to infection by a bacterium called Helicobacter pylori. The in?ammatory changes usually go after appropriate antibiotic treatment for the H. pylori infection. Acute and chronic in?ammation occurs in response to chemical damage of the gastric mucosa. For example, REFLUX of duodenal contents may predispose to in?ammatory acute and chronic gastritis. Similarly, multiple small erosions or single or multiple ulcers have resulted from consumption of chemicals, especialy aspirin and antirheumatic NONSTEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS).

Acute gastritis may cause anorexia, nausea, upper abdominal pain and, if erosive, haemorrhage. Treatment involves removal of the o?ending cause.

Chronic gastritis Accumulation of cells called round cells in the gastric mucosal characterises chronic gastritis. Most patients with chronic gastritis have no symptoms, and treatment of H. pylori infection usually cures the condition.

Atrophic gastritis A few patients with chronic gastritis may develop atrophic gastritis. With or without in?ammatory change, this disorder is common in western countries. The incidence increases with age, and more than 50 per cent of people over 50 may have it. A more complete and uniform type of ATROPHY, called ‘gastric atrophy’, characterises a familial disease called PERNICIOUS ANAEMIA. The cause of the latter disease is not known but it may be an autoimmune disorder.

Since atrophy of the corpus mucosa results in loss of acid- and pepsin-secreting cells, gastric secretion is reduced or absent. Patients with pernicious anaemia or severe atrophic gastritis of the corpus mucosa may secrete too little intrinsic factor for absorption of vitamin B12 and so can develop severe neurological disease (subacute combined degeneration of the spinal cord).

Patients with atrophic gastritis often have bacterial colonisation of the upper alimentary tract, with increased concentration of nitrite and carcinogenic N-nitroso compounds. These, coupled with excess growth of mucosal cells, may be linked to cancer. In chronic corpus gastritis, the risk of gastric cancer is about 3–4 times that of the general population.

Postgastrectomy mucosa The mucosa of the gastric remnant after surgical removal of the distal part of the stomach is usually in?amed and atrophic, and is also premalignant, with the risk of gastric cancer being very much greater than for patients with duodenal ulcer who have not had surgery.

Stress gastritis Acute stress gastritis develops, sometimes within hours, in individuals who have undergone severe physical trauma, BURNS (Curling ulcers), severe SEPSIS or major diseases such as heart attacks, strokes, intracranial trauma or operations (Cushing’s ulcers). The disorder presents with multiple super?cial erosions or ulcers of the gastric mucosa, with HAEMATEMESIS and MELAENA and sometimes with perforation when the acute ulcers erode through the stomach wall. Treatment involves inhibition of gastric secretion with intravenous infusion of an H2-receptorantagonist drug such as RANITIDINE or FAMOTIDINE, so that the gastric contents remain at a near neutral pH. Despite treatment, a few patients continue to bleed and may then require radical gastric surgery.

Gastric ulcer Gastric ulcers were common in young women during the 19th century, markedly fell in frequency in many western countries during the ?rst half of the 20th century, but remained common in coastal northern Norway, Japan, in young Australian women, and in some Andean populations. During the latter half of this century, gastric ulcers have again become more frequent in the West, with a peak incidence between 55 and 65 years.

The cause is not known. The two factors most strongly associated with the development of duodenal ulcers – gastric-acid production and gastric infection with H. pylori bacteria – are not nearly as strongly associated with gastric ulcers. The latter occur with increased frequency in individuals who take aspirin or NSAIDs. In healthy individuals who take NSAIDs, as many as 6 per cent develop a gastric ulcer during the ?rst week of treatment, while in patients with rheumatoid arthritis who are being treated long term with drugs, gastric ulcers occur in 20–40 per cent. The cause is inhibition of the enzyme cyclo-oxygenase, which in turn inhibits the production of repair-promoting PROSTAGLANDINS.

Gastric ulcers occur especially on the lesser curve of the stomach. The ulcers may erode through the whole thickness of the gastric wall, perforating into the peritoneal cavity or penetrating into liver, pancreas or colon.

Gastric ulcers usually present with a history of epigastric pain of less than one year. The pain tends to be associated with anorexia and may be aggravated by food, although patients with ‘prepyloric’ ulcers may obtain relief from eating or taking antacid preparations. Patients with gastric ulcers also complain of nausea and vomiting, and lose weight.

The principal complications of gastric ulcer are haemorrhage from arterial erosion, or perforation into the peritoneal cavity resulting in PERITONITIS, abscess or ?stula.

Aproximately one in two gastric ulcers heal ‘spontaneously’ in 2–3 months; however, up to 80 per cent of the patients relapse within 12 months. Repeated recurrence and rehealing results in scar tissue around the ulcer; this may cause a circumferential narrowing – a condition called ‘hour-glass stomach’.

The diagnosis of gastric ulcer is con?rmed by ENDOSCOPY. All patients with gastric ulcers should have multiple biopsies (see BIOPSY) to exclude the presence of malignant cells. Even after healing, gastric ulcers should be endoscopically monitored for a year.

Treatment of gastric ulcers is relatively simple: a course of one of the H2 RECEPTOR ANTAGONISTS heals gastric ulcers in 3 months. In patients who relapse, long-term inde?nite treatment with an H2 receptor antagonist such as ranitidine may be necessary since the ulcers tend to recur. Recently it has been claimed that gastric ulcers can be healed with a combination of a bismuth salt or a gastric secretory inhibitor

for example, one of the PROTON PUMP INHIBITORS such as omeprazole or lansoprazole

together with two antibiotics such as AMOXYCILLIN and METRONIDAZOLE. The long-term outcome of such treatment is not known. Partial gastrectomy, which used to be a regular treatment for gastric ulcers, is now much more rarely done unless the ulcer(s) contain precancerous cells.

Cancer of the stomach Cancer of the stomach is common and dangerous and, worldwide, accounts for approximately one in six of all deaths from cancer. There are marked geographical di?erences in frequency, with a very high incidence in Japan and low incidence in the USA. In the United Kingdom around 33 cases per 100,000 population are diagnosed annually. Studies have shown that environmental factors, rather than hereditary ones, are mainly responsible for the development of gastric cancer. Diet, including highly salted, pickled and smoked foods, and high concentrations of nitrate in food and drinking water, may well be responsible for the environmental effects.

Most gastric ulcers arise in abnormal gastric mucosa. The three mucosal disorders which especially predispose to gastric cancer include pernicious anaemia, postgastrectomy mucosa, and atrophic gastritis (see above). Around 90 per cent of gastric cancers have the microscopic appearance of abnormal mucosal cells (and are called ‘adenocarcinomas’). Most of the remainder look like endocrine cells of lymphoid tissue, although tumours with mixed microscopic appearance are common.

Early gastric cancer may be symptomless and, in countries like Japan with a high frequency of the disease, is often diagnosed during routine screening of the population. In more advanced cancers, upper abdominal pain, loss of appetite and loss of weight occur. Many present with obstructive symptoms, such as vomiting (when the pylorus is obstructed) or di?culty with swallowing. METASTASIS is obvious in up to two-thirds of patients and its presence contraindicates surgical cure. The diagnosis is made by endoscopic examination of the stomach and biopsy of abnormal-looking areas of mucosa. Treatment is surgical, often with additional chemotherapy and radiotherapy.... stomach, diseases of

Thyroid Gland, Diseases Of

... thyroid gland, diseases of

Tropical Almond

Terminalia catappa

Description: This tree grows up to 9 meters tall. Its leaves are evergreen, leathery, 45 centimeters long, 15 centimeters wide, and very shiny. It has small, yellowish- green flowers. Its fruit is flat, 10 centimeters long, and not quite as wide. The fruit is green when ripe.

Habitat and Distribution: This tree is usually found growing near the ocean. It is a common and often abundant tree in the Caribbean and Central and South America. It is also found in the tropical rain forests of southeastern Asia, northern Australia, and Polynesia.

Edible Parts: The seed is a good source of food. Remove the fleshy, green covering and eat the seed raw or cooked.... tropical almond

Gall-bladder, Diseases Of

The gall-bladder rests on the underside of the LIVER and joins the common hepatic duct via the cystic duct to form the common BILE DUCT. The gall-bladder acts as a reservoir and concentrator of BILE, alterations in the composition of which may result in the formation of gallstones, the most common disease of the gallbladder.

Gall-stones affect 22 per cent of women and 11 per cent of men. The incidence increases with age, but only about 30 per cent of those with gall-stones undergo treatment as the majority of cases are asymptomatic. There are three types of stone: cholesterol, pigment and mixed, depending upon their composition; stones are usually mixed and may contain calcium deposits. The cause of most cases is not clear but sometimes gall-stones will form around a ‘foreign body’ within the bile ducts or gall-bladder, such as suture material. BILIARY COLIC Muscle ?bres in the biliary system contract around a stone in the cystic duct or common bile duct in an attempt to expel it. This causes pain in the right upper quarter of the abdomen, with nausea and occasionally vomiting. JAUNDICE Gall-stones small enough to enter the common bile duct may block the ?ow of bile and cause jaundice. ACUTE CHOLECYSTITIS Blockage of the cystic duct may lead to this. The gall-bladder wall becomes in?amed, resulting in pain in the right upper quarter of the abdomen, fever, and an increase in the white-blood-cell count. There is characteristically tenderness over the tip of the right ninth rib on deep inhalation (Murphy’s sign). Infection of the gall-bladder may accompany the acute in?ammation and occasionally an EMPYEMA of the gall-bladder may result. CHRONIC CHOLECYSTITIS A more insidious form of gall-bladder in?ammation, producing non-speci?c symptoms of abdominal pain, nausea and ?atulence which may be worse after a fatty meal.

Diagnosis Stones are usually diagnosed on the basis of the patient’s reported symptoms, although asymptomatic gall-stones are often an incidental ?nding when investigating another complaint. Con?rmatory investigations include abdominal RADIOGRAPHY – although many gall-stones are not calci?ed and thus do not show up on these images; ULTRASOUND scanning; oral CHOLECYSTOGRAPHY – which entails a patient’s swallowing a substance opaque to X-rays which is concentrated in the gall-bladder; and endoscopic retrograde cholangiopancreatography (ERCP) – a technique in which an ENDOSCOPE is passed into the duodenum and a contrast medium injected into the biliary duct.

Treatment Biliary colic is treated with bed rest and injection of morphine-like analgesics. Once the pain has subsided, the patient may then be referred for further treatment as outlined below. Acute cholecystitis is treated by surgical removal of the gall-bladder. There are two techniques available for this procedure: ?rstly, conventional cholecystectomy, in which the abdomen is opened and the gall-bladder cut out; and, secondly, laparoscopic cholecystectomy, in which ?breoptic instruments called endoscopes (see FIBREOPTIC ENDOSCOPY) are introduced into the abdominal cavity via several small incisions (see MINIMALLY INVASIVE SURGERY (MIS)). Laparoscopic surgery has the advantage of reducing the patient’s recovery time. Gall-stones may be removed during ERCP; they can sometimes be dissolved using ultrasound waves (lithotripsy) or tablet therapy (dissolution chemotherapy). Pigment stones, calci?ed stones or stones larger than 15 mm in diameter are not suitable for this treatment, which is also less likely to succeed in the overweight patient. Drug treatment is prolonged but stones can disappear completely after two years. Stones may re-form on stopping therapy. The drugs used are derivatives of bile salts, particularly chenodeoxycholic acid; side-effects include diarrhoea and liver damage.... gall-bladder, diseases of

Notifiable Diseases

Diseases, usually of an infectious nature, which are required by law to be made known to a health o?cer or local authority. (See INFECTION.) Certain occupational diseases are also noti?able.

Noti?able diseases in the UK (For more information on a speci?c disease, refer to the separate dictionary entry.) Acute encephalitis Acute poliomyelitis Anthrax Cholera Diphtheria Dysentery (amoebic or bacillary) Ebola virus disease Food poisoning Lassa fever Leprosy (reported to Chief Medical O?cer at the Department of Health) Leptospirosis Malaria Marburg disease Measles Meningitis Meningococcal septicaemia (without meningitis) Mumps Ophthalmia neonatorum Paratyphoid fever Plague Rabies Relapsing fever Rubella Scarlet fever Smallpox Tetanus Tuberculosis Typhoid fever Typhus Viral haemorrhagic fever (including Lassa fever) Viral hepatitis Whooping cough Yellow fever

Reporting AIDS is voluntary (and in con?dence) to the Director, Communicable Diseases Surveillance Centre (PHLS).... notifiable diseases

Tropical Eosinophilia

A syndro me found in certain tropical areas in which patients present with hypereosinophilia, pulmonary infiltration, cough, chest pain and asthma-like attacks. Associated with infection by the filarial nematodes Wuchereriabancrofti and Brugia malayi. These infections are usually amicrofilaraemic, , especially in expatriates, i.e. no microfilariae can be detected in peripheral blood.... tropical eosinophilia

Tropical Sprue

A chronic malabsorptive, diarrhoeal, steatorrhoeic condition of unknown aetiology but often associated with secondary bacterial involvement.... tropical sprue

Uterus, Diseases Of

Absence or defects of the uterus

Rarely, the UTERUS may be completely absent as a result of abnormal development. In such patients secondary sexual development is normal but MENSTRUATION is absent (primary amennorhoea). The chromosomal make-up of the patient must be checked (see CHROMOSOMES; GENES): in a few cases the genotype is male (testicular feminisation syndrome). No treatment is available, although the woman should be counselled.

The uterus develops as two halves which fuse together. If the fusion is incomplete, a uterine SEPTUM results. Such patients with a double uterus (uterus didelphys) may have fertility problems which can be corrected by surgical removal of the uterine septum. Very rarely there may be two uteri with a double vagina.

The uterus of most women points forwards (anteversion) and bends forwards (ante?exion). However, about 25 per cent of women have a uterus which is pointed backwards (retroversion) and bent backwards (retro?exion). This is a normal variant and very rarely gives rise to any problems. If it does, the attitude of the uterus can be corrected by an operation called a ventrosuspension.

Endometritis The lining of the uterine cavity is called the ENDOMETRIUM. It is this layer that is partially shed cyclically in women of reproductive age giving rise to menstruation. Infection of the endometrium is called endometritis and usually occurs after a pregnancy or in association with the use of an intrauterine contraceptive device (IUCD – see CONTRACEPTION). The symptoms are usually of pain, bleeding and a fever. Treatment is with antibiotics. Unless the FALLOPIAN TUBES are involved and damaged, subsequent fertility is unaffected. Very rarely, the infection is caused by TUBERCULOSIS. Tuberculous endometritis may destroy the endometrium causing permanent amenorrhoea and sterility.

Menstrual disorders are common. Heavy periods (menorrhagia) are often caused by ?broids (see below) or adenomyosis (see below) or by anovulatory cycles. Anovulatory cycles result in the endometrium being subjected to unopposed oestrogen stimulation and occasionally undergoing hyperplasia. Treatment is with cyclical progestogens (see PROGESTOGEN) initially. If this form of treatment fails, endoscopic surgery to remove the endometrium may be successful. The endometrium may be removed using LASER (endometrial laser ablation) or electrocautery (transcervical resection of endometrium). Hysterectomy (see below) will cure the problem if endoscopic surgery fails. Adenomyosis is a condition in which endometrial tissue is found in the muscle layer (myometrium) of the uterus. It usually presents as heavy and painful periods, and occasionally pain during intercourse. Hysterectomy is usually required.

Oligomenorhoea (scanty or infrequent periods) may be caused by a variety of conditions including thyroid disease (see THYROID GLAND, DISEASES OF). It is most commonly associated with usage of the combined oral contraceptive pill. Once serious causes have been eliminated, the patient should be reassured. No treatment is necessary unless conception is desired, in which case the patient may require induction of ovulation.

Primary amenorrhoea means that the patient has never had a period. She should be investigated, although usually it is only due to an inexplicable delay in the onset of periods (delayed menarche) and not to any serious condition. Secondary amenorrhoea is the cessation of periods after menstruation has started. The most common cause is pregnancy. It may be also caused by endocrinological or hormonal problems, tuberculous endometritis, emotional problems and severe weight loss. The treatment of amenorrhoea depends on the cause.

Dysmenorrhoea, or painful periods, is the most common disorder; in most cases the cause is unknown, although the disorder may be due to excessive production of PROSTAGLANDINS.

Irregular menstruation (variations from the woman’s normal menstrual pattern or changes in the duration of bleeding or the amount) can be the result of a disturbance in the balance of OESTROGENS and PROGESTERONE hormone which between them regulate the cycle. For some time after the MENARCHE or before the MENOPAUSE, menstruation may be irregular. If irregularity occurs in a woman whose periods are normally regular, it may be due to unsuspected pregnancy, early miscarriage or to disorders in the uterus, OVARIES or pelvic cavity. The woman should seek medical advice.

Fibroids (leiomyomata) are benign tumours arising from the smooth muscle layer (myometrium) of the uterus. They are found in 80 per cent of women but only a small percentage give rise to any problems and may then require treatment. They may cause heavy periods and occasionally pain. Sometimes they present as a mass arising from the pelvis with pressure symptoms from the bladder or rectum. Although they can be shrunk medically using gonadorelin analogues, which raise the plasma concentrations of LUTEINISING HORMONE and FOLLICLE-STIMULATING HORMONE, this is not a long-term solution. In any case, ?broids only require treatment if they are large or enlarging, or if they cause symptoms. Treatment is either myomectomy (surgical removal) if fertility is to be retained, or a hysterectomy.

Uterine cancers tend to present after the age of 40 with abnormal bleeding (intermenstrual or postmenopausal bleeding). They are usually endometrial carcinomas. Eighty per cent present with early (Stage I) disease. Patients with operable cancers should be treated with total abdominal hysterectomy and bilateral excision of the ovaries and Fallopian tubes. Post-operative RADIOTHERAPY is usually given to those patients with adverse prognostic factors. Pre-operative radiotherapy is still given by some centres, although this practice is now regarded as outdated. PROGESTOGEN treatment may be extremely e?ective in cases of recurrence, but its value remains unproven when used as adjuvant treatment. In 2003 in England and Wales, more than 2,353 women died of uterine cancer.

Disorders of the cervix The cervix (neck of the womb) may produce an excessive discharge due to the presence of a cervical ectopy or ectropion. In both instances columnar epithelium – the layer of secreting cells – which usually lines the cervical canal is exposed on its surface. Asymptomatic patients do not require treatment. If treatment is required, cryocautery – local freezing of tissue – is usually e?ective.

Cervical smears are taken and examined in the laboratory to detect abnormal cells shed from the cervix. Its main purpose is to detect cervical intraepithelial neoplasia (CIN) – the presence of malignant cells in the surface tissue lining the cervix – since up to 40 per cent of women with this condition will develop cervical cancer if the CIN is left untreated. Women with abnormal smears should undergo colposcopy, a painless investigation using a low-powered microscope to inspect the cervix. If CIN is found, treatment consists of simply removing the area of abnormal skin, either using a diathermy loop or laser instrument.

Unfortunately, cervical cancer remains the most common of gynaecological cancers. The most common type is squamous cell carcinoma and around 4,000 new cases (all types) are diagnosed in England and Wales every year. As many as 50 per cent of the women affected may die from the disease within ?ve years. Cervical cancer is staged clinically in four bands according to how far it has extended, and treatment is determined by this staging. Stage I involves only the mucosal lining of the cervix and cone BIOPSY may be the best treatment in young women wanting children. In Stage IV the disease has spread beyond the cervix, uterus and pelvis to the URINARY BLADDER or RECTUM. For most women, radiotherapy or radical Wertheim’s hysterectomy – the latter being preferable for younger women – is the treatment of choice if the cancer is diagnosed early, both resulting in survival rates of ?ve years in 80 per cent of patients. Wertheim’s hysterectomy is a major operation in which the uterus, cervix, upper third of vagina and the tissue surrounding the cervix are removed together with the LYMPH NODES draining the area. The ovaries may be retained if desired. Patients with cervical cancer are treated by radiotherapy, either because they present too late for surgery or because the surgical skill to perform a radical hysterectomy is not available. These operations are best performed by gynaecological oncologists who are gynaecological surgeons specialising in the treatment of gynaecological tumours. The role of CHEMOTHERAPY in cervical and uterine cancer is still being evaluated.

Prolapse of the uterus is a disorder in which the organ drops from its normal situation down into the vagina. First-degree prolapse is a slight displacement of the uterus, second-degree a partial displacement and third-degree when the uterus can be seen outside the VULVA. It may be accompanied by a CYSTOCOELE (the bladder bulges into the front wall of the vagina), urethrocoele (the urethra bulges into the vagina) and rectocoele (the rectal wall bulges into the rear wall of the vagina). Prolapse most commonly occurs in middle-aged women who have had children, but the condition is much less common now than in the past when prenatal and obstetric care was poor, women had more pregnancies and their general health was poor. Treatment is with pelvic exercises, surgical repair of the vagina or hysterectomy. If the woman does not want or is not ?t for surgery, an internal support called a pessary can be ?tted – and changed periodically.

Vertical section of female reproductive tract (viewed from front) showing sites of common gynaecological disorders.

Hysterectomy Many serious conditions of the uterus have traditionally been treated by hysterectomy, or removal of the uterus. It remains a common surgical operation in the UK, but is being superseded in the treatment of some conditions, such as persistent MENORRHAGIA, with endometrial ablation – removal of the lining of the uterus using minimally invasive techniques, usually using an ENDOSCOPE and laser. Hysterectomy is done to treat ?broids, cancer of the uterus and cervix, menorrhagia, ENDOMETRIOSIS and sometimes for severely prolapsed uterus. Total hysterectomy is the usual type of operation: it involves the removal of the uterus and cervix and sometimes the ovaries. After hysterectomy a woman no longer menstruates and cannot become pregnant. If the ovaries have been removed as well and the woman had not reached the menopause, hormone replacement therapy (HRT – see MENOPAUSE) should be considered. Counselling helps the woman to recover from the operation which can be an emotionally challenging event for many.... uterus, diseases of

Connective Tissue Diseases

Types of autoimmune disorders that often affect blood vessels and produce secondary connective tissue damage. They include rheumatoid arthritis, systemic lupus erythematosus, polyarteritis nodosa, scleroderma, and dermatomyositis.... connective tissue diseases

Intestine, Diseases Of

The principal signs of trouble which has its origin in the intestine consist of pain somewhere about the abdomen, sometimes vomiting, and irregular bowel movements: constipation, diarrhoea or alternating bouts of these.

Several diseases and conditions are treated under separate headings. (See APPENDICITIS; CHOLERA; COLITIS; CONSTIPATION; CROHN’S DISEASE; DIARRHOEA; DYSENTERY; ENTERIC FEVER; HAEMORRHOIDS; HERNIA; INFLAMMATORY BOWEL DISEASE (IBD); ILEITIS; INTUSSUSCEPTION; IRRITABLE BOWEL SYNDROME (IBS); PERITONITIS; RECTUM, DISEASES OF; ULCERATIVE COLITIS.)

In?ammation of the outer surface is called peritonitis, a serious disease. That of the inner surface is known generally as enteritis, in?ammation of special parts receiving the names of colitis, appendicitis, irritable bowel syndrome (IBS) and in?ammatory bowel disease (IBD). Enteritis may form the chief symptom of certain infective diseases: for example in typhoid fever (see ENTERIC FEVER), cholera and dysentery. It may be acute, although not connected with any de?nite organism, when, if severe, it is a very serious condition, particularly in young children. Or it may be chronic, especially as the result of dysentery, and then constitutes a less serious if very troublesome complaint.

Perforation of the bowel may take place as the result either of injury or of disease. Stabs and other wounds which penetrate the abdomen may damage the bowel, and severe blows or crushes may tear it without any external wound. Ulceration, as in typhoid fever, or, more rarely, in TUBERCULOSIS, may cause an opening in the bowel-wall also. Again, when the bowel is greatly distended above an obstruction, faecal material may accumulate and produce ulcers, which rupture with the ordinary movements of the bowels. Whatever the cause, the symptoms are much the same.

Symptoms The contents of the bowel pass out through the perforation into the peritoneal cavity, and set up a general peritonitis. In consequence, the abdomen is painful, and after a few hours becomes extremely tender to the touch. The abdomen swells, particularly in its upper part, owing to gas having passed also into the cavity. Fever and vomiting develop and the person passes into a state of circulatory collapse or SHOCK. Such a condition may be fatal if not properly treated.

Treatment All food should be withheld and the patient given intravenous ?uids to resuscitate them and then to maintain their hydration and electrolyte balance. An operation is urgently necessary, the abdomen being opened in the middle line, the perforated portion of bowel found, the perforation stitched up, and appropriate antibiotics given.

Obstruction means a stoppage to the passage down the intestine of partially digested food. Obstruction may be acute, when it comes on suddenly with intense symptoms; or it may be chronic, when the obstructing cause gradually increases and the bowel becomes slowly more narrow until it closes altogether; or subacute, when obstruction comes and goes until it ends in an acute attack. In chronic cases the symptoms are milder in degree and more prolonged.

Causes Obstruction may be due to causes outside the bowel altogether, for example, the pressure of tumours in neighbouring organs, the twisting around the bowel of bands produced by former peritonitis, or even the twisting of a coil of intestine around itself so as to cause a kink in its wall. Chronic causes of the obstruction may exist in the wall of the bowel itself: for example, a tumour, or the contracting scar of an old ulcer. The condition of INTUSSUSCEPTION, where part of the bowel passes inside of the part beneath it, in the same way as one turns the ?nger of a glove outside in, causes obstruction and other symptoms. Bowel within a hernia may become obstructed when the hernia strangulates. Finally some body, such as a concretion, or the stone of some large fruit, or even a mass of hardened faeces, may become jammed within the bowel and stop up its passage.

Symptoms There are four chief symptoms: pain, vomiting, constipation and swelling of the abdomen.

Treatment As a rule the surgeon opens the abdomen, ?nds the obstruction and relieves it or if possible removes it altogether. It may be necessary to form a COLOSTOMY or ILEOSTOMY as a temporary or permanent measure in severe cases.

Tumours are rare in the small intestine and usually benign. They are relatively common in the large intestine and are usually cancerous. The most common site is the rectum. Cancer of the intestine is a disease of older people; it is the second most common cancer (after breast cancer) in women in the United Kingdom, and the third most common (after lung and prostate) in men. Around 25,000 cases of cancer of the large intestine occur in the UK annually, about 65 per cent of which are in the colon. A history of altered bowel habit, in the form of increasing constipation or diarrhoea, or an alternation of these, or of bleeding from the anus, in a middle-aged person is an indication for taking medical advice. If the condition is cancer, then the sooner it is investigated and treated, the better the result.... intestine, diseases of

Kidneys, Diseases Of

Diseases affecting the kidneys can be broadly classi?ed into congenital and genetic disorders; autoimmune disorders; malfunctions caused by impaired blood supply; infections; metabolic disorders; and tumours of the kidney. Outside factors may cause functional disturbances – for example, obstruction in the urinary tract preventing normal urinary ?ow may result in hydronephrosis (see below), and the CRUSH SYNDROME, which releases proteins into the blood as a result of seriously damaged muscles (rhabdomyolosis), can result in impaired kidney function. Another outside factor, medicinal drugs, can also be hazardous to the kidney. Large quantities of ANALGESICS taken over a long time damage the kidneys and acute tubular NECROSIS can result from certain antibiotics.

K

Diagram of glomerulus (Malpighian corpuscle).

Fortunately the body has two kidneys and, as most people can survive on one, there is a good ‘functional reserve’ of kidney tissue.

Symptoms Many patients with kidney disorders do not have any symptoms, even when the condition is quite advanced. However,

others experience loin pain associated with obstruction (renal colic) or due to infection; fevers; swelling (oedema), usually of the legs but occasionally including the face and arms; blood in the urine (haematuria); and excess quantities of urine (polyuria), including at night (nocturia), due to failure of normal mechanisms in the kidney for concentrating urine. Patients with chronic renal failure often have very di?use symptoms including nausea and vomiting, tiredness due to ANAEMIA, shortness of breath, skin irritation, pins and needles (paraesthesia) due to damage of the peripheral nerves (peripheral neuropathy), and eventually (rarely seen nowadays) clouding of consciousness and death.

Signs of kidney disease include loin tenderness, enlarged kidneys, signs of ?uid retention, high blood pressure and, in patients with end-stage renal failure, pallor, pigmentation and a variety of neurological signs including absent re?exes, reduced sensation, and a coarse ?apping tremor (asterixis) due to severe disturbance of the body’s normal metabolism.

Renal failure Serious kidney disease may lead to impairment or failure of the kidney’s ability to ?lter waste products from the blood and excrete them in the urine – a process that controls the body’s water and salt balance and helps to maintain a stable blood pressure. Failure of this process causes URAEMIA – an increase in urea and other metabolic waste products – as well as other metabolic upsets in the blood and tissues, all of which produce varying symptoms. Failure can be sudden or develop more slowly (chronic). In the former, function usually returns to normal once the underlying cause has been treated. Chronic failure, however, usually irreparably reduces or stops normal function.

Acute failure commonly results from physiological shock following a bad injury or major illness. Serious bleeding or burns can reduce blood volume and pressure to the point where blood-supply to the kidney is greatly reduced. Acute myocardial infarction (see HEART, DISEASES OF) or pancreatitis (see PANCREAS, DISORDERS OF) may produce a similar result. A mismatched blood transfusion can produce acute failure. Obstruction to the urine-?ow by a stone (calculus) in the urinary tract, a bladder tumour or an enlarged prostate can also cause acute renal failure, as can glomerulonephritis (see below) and the haemolytic-uraemia syndrome.

HYPERTENSION, DIABETES MELLITUS, polycystic kidney disease (see below) or AMYLOIDOSIS are among conditions that cause chronic renal failure. Others include stone, tumour, prostatic enlargement and overuse of analgesic drugs. Chronic failure may eventually lead to end-stage renal failure, a life-threatening situation that will need DIALYSIS or a renal transplant (see TRANSPLANTATION).

Familial renal disorders include autosomal dominant inherited polycystic kidney disease and sex-linked familial nephropathy. Polycystic kidney disease is an important cause of renal failure in the UK. Patients, usually aged 30–50, present with HAEMATURIA, loin or abdominal discomfort or, rarely, urinary-tract infection, hypertension and enlarged kidneys. Diagnosis is based on ultrasound examination of the abdomen. Complications include renal failure, hepatic cysts and, rarely, SUBARACHNOID HAEMORRHAGE. No speci?c treatment is available. Familial nephropathy occurs more often in boys than in girls and commonly presents as Alport’s syndrome (familial nephritis with nerve DEAFNESS) with PROTEINURIA, haematuria, progressing to renal failure and deafness. The cause of the disease lies in an absence of a speci?c ANTIGEN in a part of the glomerulus. The treatment is conservative, with most patients eventually requiring dialysis or transplantation.

Acute glomerulonephritis is an immune-complex disorder due to entrapment within glomerular capillaries of ANTIGEN (usually derived from B haemolytic streptococci – see STREPTOCOCCUS) antibody complexes initiating an acute in?ammatory response (see IMMUNITY). The disease affects children and young adults, and classically presents with a sore throat followed two weeks later by a fall in urine output (oliguria), haematuria, hypertension and mildly abnormal renal function. The disease is self-limiting with 90 per cent of patients spontaneously recovering. Treatment consists of control of blood pressure, reduced ?uid and salt intake, and occasional DIURETICS and ANTIBIOTICS.

Chronic glomerulonephritis is also due to immunological renal problems and is also classi?ed by taking a renal biopsy. It may be subdivided into various histological varieties as determined by renal biospy. Proteinuria of various degrees is present in all these conditions but the clinical presentations vary, as do their treatments. Some resolve spontaneously; others are treated with steroids or even the cytotoxic drug CYCLOPHOSPHAMIDE or the immunosuppressant cyclosporin. Prognoses are generally satisfactory but some patients may require renal dialysis or kidney transplantation – an operation with a good success rate.

Hydronephrosis A chronic disease in which the kidney becomes greatly distended with ?uid. It is caused by obstruction to the ?ow of urine at the pelvi-ureteric junction (see KIDNEYS – Structure). If the ureter is obstructed, the ureter proximal to the obstruction will dilate and pressure will be transmitted back to the kidney to cause hydronephrosis. Obstruction may occur at the bladder neck or in the urethra itself. Enlargement of the prostate is a common cause of bladder-neck obstruction; this would give rise to hypertrophy of the bladder muscle and both dilatation of the ureter and hydronephrosis. If the obstruction is not relieved, progressive destruction of renal tissue will occur. As a result of the stagnation of the urine, infection is probable and CYSTITIS and PYELONEPHRITIS may occur.

Impaired blood supply may be the outcome of diabetes mellitus and physiological shock, which lowers the blood pressure, also affecting the blood supply. The result can be acute tubular necrosis. POLYARTERITIS NODOSA and SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) may damage the large blood vessels in the kidney. Treatment is of the underlying condition.

Infection of the kidney is called pyelonephritis, a key predisposing factor being obstruction of urine ?ow through the urinary tract. This causes stagnation and provides a fertile ground for bacterial growth. Acute pyelonephritis is more common in women, especially during pregnancy when bladder infection (CYSTITIS) spreads up the ureters to the kidney. Symptoms are fever, malaise and backache. Antibiotics and high ?uid intake are the most e?ective treatment. Chronic pyelonephritis may start in childhood as a result of congenital deformities that permit urine to ?ow up from the bladder to the kidney (re?ux). Persistent re?ux leads to recurrent infections causing permanent damage to the kidney. Specialist investigations are usually required as possible complications include hypertension and kidney failure.

Tumours of the kidney are fortunately rare. Non-malignant ones commonly do not cause symptoms, and even malignant tumours (renal cell carcinoma) may be asymptomatic for many years. As soon as symptoms appear – haematuria, back pain, nausea, malaise, sometimes secondary growths in the lungs, bones or liver, and weight loss – urgent treatment including surgery, radiotherapy and chemotherapy is necessary. This cancer occurs mostly in adults over 40 and has a hereditary element. The prognosis is not good unless diagnosed early. In young children a rare cancer called nephroblastoma (Wilm’s tumour) can occur; treatment is with surgery, radiotherapy and chemotherapy. It may grow to a substantial size before being diagnosed.

Cystinuria is an inherited metabolic defect in the renal tubular reabsorption of cystine, ornithine, lysine and arginine. Cystine precipitates in an alkaline urine to form cystine stones. Triple phosphate stones are associated with infection and may develop into a very large branching calculi (staghorn calculi). Stones present as renal or ureteric pain, or as an infection. Treatment has undergone considerable change with the introduction of MINIMALLY INVASIVE SURGERY (MIS) and the destruction of stone by sound waves (LITHOTRIPSY).... kidneys, diseases of

Dust Diseases

Lung disorders caused by dust particles inhaled and absorbed into the lung tissues. There they may cause fibrosis (formation of scar tissue) and progressive lung damage. The main symptoms are a cough and breathing difficulty. It may take at least 10 years of exposure to dusts containing coal, silica, talc, or asbestos before serious lung damage develops (see pneumoconiosis). Hypersensitivity to moulds on hay or grain may lead to allergic alveolitis. Preventive measures, such as the installation of dust extraction machinery, have reduced the incidence of dust diseases.... dust diseases

Slow Virus Diseases

A group of diseases of the central nervous system that occur many months or even years after infection with a virus. They cause gradual widespread destruction of nerve tissue, with progressive loss of brain function and a fatal outcome. Examples include Creutzfeldt–Jakob disease and kuru.... slow virus diseases

Tropical Abscess

(amoebic abscess) an abscess of the liver caused by infection with *Entamoeba histolytica. See dysentery.... tropical abscess

Joints, Diseases Of

‘Rheumatism’ is the colloquial term for nonspeci?c musculoskeletal symptoms arising in the joints, ligaments, tendons and muscles. ‘Arthritis’ describes a pathological musculoskeletal disorder. Most common are sprains of ligaments, strains of tendons and muscles,

BURSITIS, TENDINITIS and non-speci?c back pain (see BACKACHE).

Osteoarthritis (OA) rarely starts before 40, but by the age of 80 affects 80 per cent of the population. There are structural and functional changes in the articular cartilage, as well as changes in the collagenous matrix of tendons and ligaments. OA is not purely ‘wear and tear’; various sub-groups have a genetic component. Early OA may be precipitated by localised alteration in anatomy, such as a fracture or infection of a joint. Reactive new bone growth typically occurs, causing sclerosis (hardening) beneath the joint, and osteophytes – outgrowths of bone – are characteristic at the margins of the joint. The most common sites are the ?rst metatarsal (great toe), spinal facet joints, the knee, the base of the thumb and the terminal ?nger joints (Heberden’s nodes).

OA has a slow but variable course, with periods of pain and low-grade in?ammation. Acute in?ammation, common in the knee, may result from release of pyrophosphate crystals, causing pseudo-gout.

Urate gout results from crystallisation of URIC ACID in joints, against a background of hyperuricaemia. This high concentration of uric acid in the blood may result from genetic and environmental factors, such as excess dietary purines, alcohol or diuretic drugs.

In?ammatory arthritis is less common than OA, but potentially much more serious. Several types exist, including: SPONDYLARTHRITIS This affects younger men, chie?y involving spinal and leg joints. This may lead to in?ammation and eventual ossi?cation of the enthesis – that is, where the ligaments and tendons are inserted into the bone around joints. This may be associated with disorders in other parts of the body: skin in?ammation (PSORIASIS), bowel and genito-urinary in?ammation, sometimes resulting in infection of the organs (such as dysentery). The syndromes most clearly delineated are ankylosing spondylitis (see SPINE AND SPINAL CORD, DISEASES AND INJURIES OF), psoriatic or colitic spondylitis, and REITER’S SYNDROME. The diagnosis is made clinically and radiologically; no association has been found with autoantibodies (see AUTOANTIBODY). A particularly clear gene locus, HLA B27, has been identi?ed in ankylosing spondylitis. Psoriasis can be associated with a characteristic peripheral arthritis.

Systemic autoimmune rheumatic diseases (see AUTOIMMUNE DISORDERS). RHEUMATOID ARTHRITIS (RA) – see also main entry. The most common of these diseases. Acute in?ammation causes lymphoid synovitis, leading to erosion of the cartilage, associated joints and soft tissues. Fibrosis follows, causing deformity. Autoantibodies are common, particularly Rheumatoid Factor. A common complication of RA is Sjögren’s syndrome, when in?ammation of the mucosal glands may result in a dry mouth and eyes. SYSTEMIC LUPUS ERYTHEMATOSUS (SLE) and various overlap syndromes occur, such as systemic sclerosis and dermatomyositis. Autoantibodies against nuclear proteins such as DNA lead to deposits of immune complexes and VASCULITIS in various tissues, such as kidney, brain, skin and lungs. This may lead to various symptoms, and sometimes even to organ failure.

Infective arthritis includes: SEPTIC ARTHRITIS An uncommon but potentially fatal disease if not diagnosed and treated early with approriate antibiotics. Common causes are TUBERCLE bacilli and staphylococci (see STAPHYLOCOCCUS). Particularly at risk are the elderly and the immunologically vulnerable, such as those under treatment for cancer, or on CORTICOSTEROIDS or IMMUNOSUPPRESSANT drugs. RHEUMATIC FEVER Now rare in western countries. Resulting from an immunological reaction to a streptococcal infection, it is characterised by migratory arthritis, rash and cardiac involvement.

Other infections which may be associated with arthritis include rubella (German measles), parvovirus and LYME DISEASE.

Treatment Septic arthritis is the only type that can be cured using antibiotics, while the principles of treatment for the others are similar: to reduce risk factors (such as hyperuricaemia); to suppress in?ammation; to improve function with physiotherapy; and, in the event of joint failure, to perform surgical arthroplasty. NON-STEROIDAL ANTI-INFLAMMATORY DRUGS (NSAIDS) include aspirin, paracetamol and many recently developed ones, such as the proprionic acid derivatives IBUPROFEN and naproxen, along with other drugs that have similar properties such as PIROXICAM. They all carry a risk of toxicity, such as renal dysfunction, or gastrointestinal irritation with haemorrhage. Stronger suppression of in?ammation requires corticosteroids and CYTOTOXIC drugs such as azathioprine or cyclophosphamide. Recent research promises more speci?c and less toxic anti-in?ammatory drugs, such as the monoclonal antibodies like in?iximab. An important treatment for some osteoarthritic joints is surgical replacement of the joints.... joints, diseases of

Liver, Diseases Of

The LIVER may be extensively diseased without any obviously serious symptoms, unless the circulation through it is impeded, the out?ow of BILE checked, or neighbouring organs implicated. JAUNDICE is a symptom of several liver disorders, and is discussed under its separate heading. ASCITES, which may be caused by interference with the circulation through the portal vein of the liver, as well as by other reasons, is also considered separately. The presence of gallstones is a complication of some diseases connected with the liver, and is treated under GALLBLADDER, DISEASES OF. For hydatid cyst of the liver, see TAENIASIS. Liver diseases in a tropical environment are dealt with later in this section.

In?ammation of the liver, or HEPATITIS, may occur as part of a generalised infection or may be a localised condition. Infectious hepatitis, which is the result of infection with a virus, is one of the most common forms. Many di?erent viruses can cause hepatitis, including that responsible for glandular fever (see MONONUCLEOSIS). Certain spirochaetes may also be the cause, particularly that responsible for LEPTOSPIROSIS, as can many drugs. Hepatitis may also occur if there is obstruction of the BILE DUCT, as by a gall-stone.

Cirrhosis of the liver A disorder caused by chronic damage to liver cells. The liver develops areas of ?brosis or scarring; in response, the remaining normal liver cells increase and form regeneration nodules. Those islands of normality, however, suffer from inadequate blood supply, thus adversely affecting liver function. Alcohol is the most common cause of cirrhosis in the United Kingdom and the USA, and the incidence of the disorder among women in the UK has recently risen sharply as a consequence of greater consumption of alcohol by young women in the latter decades of the 20th century. In Africa and many parts of Asia, infection with hepatitis B virus is a common cause. Certain drugs – for example, PARACETAMOL – may damage the liver if taken in excess. Unusual causes of cirrhosis include defects of the bile ducts, HAEMOCHROMATOSIS (raised iron absorption from the gut), CYSTIC FIBROSIS, cardiac cirrhosis (the result of heart failure causing circulatory congestion in the liver), and WILSON’S DISEASE (raised copper absorption).

Symptoms Some people with cirrhosis have no signs or symptoms and the disease may be diagnosed at a routine medical examination. Others may develop jaundice, OEDEMA (including ascites – ?uid in the abdomen), fever, confusion, HAEMATEMESIS (vomiting blood), loss of appetite and lethargy. On examination, cirrhotic patients often have an enlarged liver and/ or SPLEEN, and HYPERTENSION. Liver function tests, cholangiography (X-ray examination of the bile ducts) and biopsy of liver tissue will help to reach a diagnosis.

Treatment Nothing can be done to repair a cirrhosed organ, but the cause, if known, must be removed and further advance of the process thus prevented. In the case of the liver, a high-protein, high-carbohydrate, low-fat diet is given, supplemented by liver extract and vitamins B and K. The consumption of alcohol should be banned. In patients with liver failure and a poor prognosis, liver TRANSPLANTATION is worthwhile but only after careful consideration.

Abscess of the liver When an ABSCESS develops in the liver, it is usually a result of amoebic DYSENTERY, appearing sometimes late in the disease – even after the diarrhoea is cured (see below). It may also follow upon in?ammation of the liver due to other causes. In the case of an amoebic abscess, treatment consists of oral metronidazole.

Acute hepatic necrosis is a destructive and often fatal disease of the liver which is very rare. It may be due to chemical poisons, such as carbontetrachloride, chloroform, phosphorus and industrial solvents derived from benzene. It may also be the cause of death in cases of poisoning with fungi. Very occasionally, it may be a complication of acute infectious hepatitis.

Cancer of the liver is not uncommon, although it is rare for the disease to begin in the liver – the involvement of this organ being usually secondary to disease situated somewhere in the stomach or bowels. Cancer originating in the liver is more common in Asia and Africa. It usually arises in a ?brotic (or cirrhotic) liver and in carriers of the hepatitis B virus. There is great emaciation, which increases as the disease progresses. The liver is much enlarged, and its margin and surface are rough, being studded with hard cancer masses of varying size, which can often be felt through the abdominal wall. Pain may be present. Jaundice and oedema often appear.... liver, diseases of

Oesophagus, Diseases Of

Oesophagitis is in?ammation of the OESOPHAGUS and may be due to swallowing a corrosive chemical (corrosive oesophagitis) or because the muscles of the lower part of the oesophagus do not work properly (ACHALASIA), allowing the stomach’s acidic contents to regurgitate (re?ux oesophagitis). HIATUS HERNIA is sometimes associated with the latter condition. Diagnosis can be made by ENDOSCOPY of the oesophagus and/or an X-ray examination using a barium swallow. Treatment of re?ux oesophagitis is by an appropriate diet and weight loss. Stricture of the oesophagus can result from swallowing a corrosive ?uid and may produce severe narrowing. Such strictures may sometimes be dilated by the use of suitable instruments; otherwise, surgery may be necessary.

A still more serious and frequent cause of oesophageal stricture is that due to cancer, which may occur at any part, but is most common at the lower end, near the entrance into the stomach. The chief symptoms of this condition are increasing di?culty in swallowing, increasing debility, together with enlargement of the glands in the neck. The condition usually occurs in middle age or beyond and around 5,000 people are diagnosed with such cancer every year in the United Kingdom. In many cases treatment can only be palliative, but recent advances in surgery are producing promising results. In some cases treatment with irradiation or anti-cancer drugs produces relief, if not cure. In those in whom neither operation nor radiation can be performed, life may be prolonged and freedom from pain obtained by ?uid food which is either swallowed or passed down a tube. In cases of achalasia (see above), the passage of a special bougie down the oesophagus to dilate the sphincter may be e?ective.

Strictures of the oesophagus may also be produced by the pressure of tumours or aneurysms within the cavity of the chest but external to the gullet.

Finally, di?culty in swallowing sometimes occurs in certain serious nervous diseases from paralysis affecting the nerves supplying the muscular coats of the PHARYNX, which thus loses its propulsive power (bulbar paralysis).

Foreign bodies which lodge in the respiratory part of the throat – i.e. at the entrance to, or in the cavity of, the larynx – set up immediate symptoms of CHOKING. Those which lodge in the gullet, on the contrary, do not usually set up any immediately serious symptoms, although their presence causes considerable discomfort. Medical attention is usually required.... oesophagus, diseases of

Lungs, Diseases Of

Various conditions affecting the LUNGS are dealt with under the following headings: ASTHMA; BRONCHIECTASIS; CHEST, DEFORMITIES OF; CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD); COLD, COMMON; EMPHYSEMA; EXPECTORATION; HAEMOPTYSIS; HAEMORRHAGE; OCCUPATIONAL HEALTH, MEDICINE AND DISEASES; PLEURISY; PNEUMONIA; PULMONARY EMBOLISM; TUBERCULOSIS.

In?ammation of the lungs is generally known as PNEUMONIA, when it is due to infection; as ALVEOLITIS when the in?ammation is immunological; and as PNEUMONITIS when it is due to physical or chemical agents.

Abscess of the lung consists of a collection of PUS within the lung tissue. Causes include inadequate treatment of pneumonia, inhalation of vomit, obstruction of the bronchial tubes by tumours and foreign bodies, pulmonary emboli (see EMBOLISM) and septic emboli. The patient becomes generally unwell with cough and fever. BRONCHOSCOPY is frequently performed to detect any obstruction to the bronchi. Treatment is with a prolonged course of antibiotics. Rarely, surgery is necessary.

Pulmonary oedema is the accumulation of ?uid in the pulmonary tissues and air spaces. This may be caused by cardiac disease (heart failure or disease of heart valves – see below, and HEART, DISEASES OF) or by an increase in the permeability of the pulmonary capillaries allowing leakage of ?uid into the lung tissue (see ACUTE RESPIRATORY DISTRESS SYNDROME (ARDS)).

Heart failure (left ventricular failure) can be caused by a weakness in the pumping action of the HEART leading to an increase in back pressure which forces ?uid out of the blood vessels into the lung tissue. Causes include heart attacks and HYPERTENSION (high blood pressure). Narrowed or leaking heart valves hinder the ?ow of blood through the heart; again, this produces an increase in back pressure which raises the capillary pressure in the pulmonary vessels and causes ?ooding of ?uid into the interstitial spaces and alveoli. Accumulation of ?uid in lung tissue produces breathlessness. Treatments include DIURETICS and other drugs to aid the pumping action of the heart. Surgical valve replacement may help when heart failure is due to valvular heart disease.

Acute respiratory distress syndrome Formerly known as adult respiratory distress syndrome (ARDS), this produces pulmonary congestion because of leakage of ?uid through pulmonary capillaries. It complicates a variety of illnesses such as sepsis, trauma, aspiration of gastric contents and di?use pneumonia. Treatment involves treating the cause and supporting the patient by providing oxygen.

Collapse of the lung may occur due to blockage of a bronchial tube by tumour, foreign body or a plug of mucus which may occur in bronchitis or pneumonia. Air beyond the blockage is absorbed into the circulation, causing the affected area of lung to collapse. Collapse may also occur when air is allowed into the pleural space – the space between the lining of the lung and the lining of the inside of the chest wall. This is called a pneumothorax and may occur following trauma, or spontaneously

– for example, when there is a rupture of a subpleural air pocket (such as a cyst) allowing a communication between the airways and the pleural space. Lung collapse by compression may occur when ?uid collects in the pleural space (pleural e?usion): when this ?uid is blood, it is known as a haemothorax; if it is due to pus it is known as an empyema. Collections of air, blood, pus or other ?uid can be removed from the pleural space by insertion of a chest drain, thus allowing the lung to re-expand.

Tumours of the lung are the most common cause of cancer in men and, along with breast cancer, are a major cause of cancer in women. Several types of lung cancer occur, the most common being squamous cell carcinoma, small- (or oat-) cell carcinoma, adenocarcinoma, and large-cell carcinoma. All but the adenocarcinoma have a strong link with smoking. Each type has a di?erent pattern of growth and responds di?erently to treatment. More than 30,000 men and women die of cancer of the trachea, bronchus and lung annually in England and Wales.

The most common presenting symptom is cough; others include haemoptisis (coughing up blood), breathlessness, chest pain, wheezing and weight loss. As well as spreading locally in the lung – the rate of spread varies – lung cancer commonly spawns secondary growths in the liver, bones or brain. Diagnosis is con?rmed by X-rays and bronchoscopy with biopsy.

Treatment Treatment for the two main categories of lung cancer – small-cell and nonsmall-cell cancer – is di?erent. Surgery is the only curative treatment for the latter and should be considered in all cases, even though fewer than half undergoing surgery will survive ?ve years. In those patients unsuitable for surgery, radical RADIOTHERAPY should be considered. For other patients the aim should be the control of symptoms and the maintenance of quality of life, with palliative radiotherapy one of the options.

Small-cell lung cancer progresses rapidly, and untreated patients survive for only a few months. Because the disease is often widespread by the time of diagnosis, surgery is rarely an option. All patients should be considered for CHEMOTHERAPY which improves symptoms and prolongs survival.

Wounds of the lung may cause damage to the lung and, by admitting air into the pleural cavity, cause the lung to collapse with air in the pleural space (pneumothorax). This may require the insertion of a chest drain to remove the air from the pleural space and allow the lung to re-expand. The lung may be wounded by the end of a fractured rib or by some sharp object such as a knife pushed between the ribs.... lungs, diseases of

Mouth, Diseases Of

The mucous membrane of the mouth can indicate the health of the individual and internal organs. For example, pallor or pigmentation may indicate ANAEMIA, JAUNDICE or ADDISON’S DISEASE.

Thrush is characterised by the presence of white patches on the mucous membrane which bleeds if the patch is gently removed. It is caused by the growth of a parasitic mould known as Candida albicans. Antifungal agents usually suppress the growth of candida. Candidal in?ltration of the mucosa is often found in cancerous lesions.

Leukoplakia literally means a white patch. In the mouth it is often due to an area of thickened cells from the horny layer of the epithelium. It appears as a white patch of varying density and is often grooved by dense ?ssures. There are many causes, most of them of minor importance. It may be associated with smoking, SYPHILIS, chronic SEPSIS or trauma from a sharp tooth. Cancer must be excluded.

Stomatitis (in?ammation of the mouth) arises from the same causes as in?ammation elsewhere, but among the main causes are the cutting of teeth in children, sharp or broken teeth, excess alcohol, tobacco smoking and general ill-health. The mucous membrane becomes red, swollen and tender and ulcers may appear. Treatment consists mainly of preventing secondary infection supervening before the stomatitis has resolved. Antiseptic mouthwashes are usually su?cient.

Gingivitis (see TEETH, DISEASES OF) is in?ammation of the gum where it touches the tooth. It is caused by poor oral hygiene and is often associated with the production of calculus or tartar on the teeth. If it is neglected it will proceed to periodontal disease.

Ulcers of the mouth These are usually small and arise from a variety of causes. Aphthous ulcers are the most common; they last about ten days and usually heal without scarring. They may be associated with STRESS or DYSPEPSIA. There is no ideal treatment.

Herpetic ulcers (see HERPES SIMPLEX) are similar but usually there are many ulcers and the patient appears feverish and unwell. This condition is more common in children.

Calculus (a) Salivary: a calculus (stone) may develop in one of the major salivary-gland ducts. This may result in a blockage which will cause the gland to swell and be painful. It usually swells before a meal and then slowly subsides. The stone may be passed but often has to be removed in a minor operation. If the gland behind the calculus becomes infected, then an ABSCESS forms and, if this persists, the removal of the gland may be indicated. (b) Dental, also called TARTAR: this is a calci?ed material which adheres to the teeth; it often starts as the soft debris found on teeth which have not been well cleaned and is called plaque. If not removed, it will gradually destroy the periodontal membrane and result in the loss of the tooth. (See TEETH, DISORDERS OF.)

Ranula This is a cyst-like swelling found in the ?oor of the mouth. It is often caused by mild trauma to the salivary glands with the result that saliva collects in the cyst instead of discharging into the mouth. Surgery may be required.

Mumps is an acute infective disorder of the major salivary glands. It causes painful enlargement of the glands which lasts for about two weeks. (See also main entry for MUMPS.)

Tumours may occur in all parts of the mouth, and may be BENIGN or MALIGNANT. Benign tumours are common and may follow mild trauma or be an exaggerated response to irritation. Polyps are found in the cheeks and on the tongue and become a nuisance as they may be bitten frequently. They are easily excised.

A MUCOCOELE is found mainly in the lower lip.

An exostosis or bone outgrowth is often found in the mid line of the palate and on the inside of the mandible (bone of the lower jaw). This only requires removal if it becomes unduly large or pointed and easily ulcerated.

Malignant tumours within the mouth are often large before they are noticed, whereas those on the lips are usually seen early and are more easily treated. The cancer may arise from any of the tissues found in the mouth including epithelium, bone, salivary tissue and tooth-forming tissue remnants. Oral cancers represent about 5 per cent of all reported malignancies, and in England and Wales around 3,300 people are diagnosed annually as having cancer of the mouth and PHARYNX.

Cancer of the mouth is less common below the age of 40 years and is more common in men. It is often associated with chronic irritation from a broken tooth or ill-?tting denture. It is also more common in those who smoke and those who chew betel leaves. Leukoplakia (see above) may be a precursor of cancer. Spread of the cancer is by way of the lymph nodes in the neck. Early treatment by surgery, radiotherapy or chemotherapy will often be e?ective, except for the posterior of the tongue where the prognosis is very poor. Although surgery may be extensive and potentially mutilating, recent advances in repairing defects and grafting tissues from elsewhere have made treatment more acceptable to the patient.... mouth, diseases of

Ovaries, Diseases Of

Oöphoritis (infection of the ovaries) rarely occurs alone, except in viral infections such as mumps. Usually it is associated with infection of the FALLOPIAN TUBES (SALPINGITIS). It may occur as a complication of a miscarriage, a therapeutic abortion, or the birth of a baby. Cases not associated with pregnancy typically result from sexual activity: the most common organisms involved are Chlamydia, E. coli, and Neisseria gonorrhoea. Cervical swabs should be sent for culture and analgesics given, together with the appropriate antibiotics.

Failure of OVULATION is the cause of INFERTILITY in around a third of couples seeking help with conception. It may also lead to menstrual problems (see MENSTRUATION), such as an irregular menstrual cycle or MENORRHAGIA. An uncommon cause of failure of ovulation is POLYCYSTIC OVARY SYNDROME, often associated with acne, hirsutism, and obesity. Treatment depends on the symptoms. Early ovarian failure is the cause of premature MENOPAUSE. Treatment consists of hormone replacement therapy using a combination of oestrogen and progestogen.

Ovarian cysts (for example, follicular cysts) result from ovulation. They may be symptomless but sometimes cause abdominal pain, pain during intercourse or disturbances in menstruation. Twisting or rupture can cause severe pain, pyrexia (fever) and nausea, and explorative surgery – endoscopic laparotomy – may be needed to establish a diagnosis (symptoms of ECTOPIC PREGNANCY are similar). The ovary may have to be removed. Simple cysts often disappear of their own accord but a large cyst can cause pressure on surrounding structures and therefore should be surgically removed.

In young women the most common benign tumour is a dermoid cyst, while in older women, ?broma (see under UTERUS, DISEASES OF) is more common. All benign tumours should be removed surgically in order to be sure they are not malignant.

Malignant tumours may be primary (arising in the ovary) or secondary (metastases from a cancer developing in another organ). Treatment depends upon the site and type of the primary tumour.

Around 5,000 women a year are diagnosed as having ovarian cancer in England and Wales. Unfortunately it is not readily detected in its early stages; around 85 per cent of women do not see a doctor until after the tumour has spread. Early tumours present with symptoms similar to benign tumours, while late ones present with abdominal distension, pain and vague gastrointestinal symptoms. The disease is most common in menopausal women. Earlier diagnosis and treatment can be achieved by ULTRASOUND screening. Treatment is surgical, aimed at totally removing the tumour mass. Nowadays RADIOTHERAPY is only used for palliation. CHEMOTHERAPY is often given to patients with ovarian metastases, or who have residual disease after surgery. The most active cytotoxic agent is the taxane, PACLITAXEL – especially when it is combined with cisplatin.... ovaries, diseases of

Prostate Gland, Diseases Of

Disease of the PROSTATE GLAND can affect the ?ow of URINE so that patients present with urological symptoms.

Prostatitis This can be either acute or chronic. Acute prostatitis is caused by a bacterial infection, while chronic prostatitis may follow on from an acute attack, arise insidiously, or be non-bacterial in origin.

Symptoms Typically the patient has pain in the PERINEUM, groins, or supra pubic region, and pain on EJACULATION. He may also have urinary frequency, and urgency.

Treatment Acute and chronic prostatitis are treated with a prolonged course of antibiotics. Patients with chronic prostatitis may also require anti-in?ammatory drugs, and antidepressants.

Prostatic enlargement This is the result of benign prostatic hyperplasia (BPH), causing enlargement of the prostate. The exact cause of this enlargement is unknown, but it affects 50 per cent of men between 40 and 59 years and 95 per cent of men over 70 years.

Symptoms These are urinary hesitancy, poor urinary stream, terminal dribbling, frequency and urgency of urination and the need to pass urine at night (nocturia). The diagnosis is made from the patient’s history; a digital examination of the prostate gland via the rectum to assess enlargement; and analysis of the urinary ?ow rate.

Treatment This can be with tablets, which either shrink the prostate – an anti-androgen drug such as ?nasteride – or relax the urinary sphincter muscle during urination. For more severe symptoms the prostate can be removed surgically, by transurethral resection of prostate (TURP), using either electrocautery or laser energy. A new treatment is the use of microwaves to heat up and shrink the enlarged gland.

Cancer Cancer of the prostate is the fourth most common cause of death from cancer in northern European males: more than 10,000 cases are diagnosed every year in the UK and the incidence is rising by 3 per cent annually.

Little is known about the cause, but the majority of prostate cancers require the male hormones, androgens, to grow.

Symptoms These are similar to those resulting from benign prostatic hypertrophy (see above). Spread of the cancer to bones can cause pain. The use of a blood test measuring the amount of an ANTIGEN, PROSTATE SPECIFIC ANTIGEN (PSA), can be helpful in making the diagnosis – as can an ULTRASOUND scan of the prostate.

Treatment This could be surgical, with removal of the prostate (either via an abdominal incision, total prostatectomy, or transurethrally), or could be by radiotherapy. In more advanced cancers, treatment with anti-androgen drugs, such as cyprotexone acetate or certain oestrogens, is used to inhibit the growth of the cancer.... prostate gland, diseases of

Psychosomatic Diseases

Taken at face value, the term ‘psychosomatic’ simply means the interaction of psyche (mind) and soma (body). As such it is a noncontroversial concept that points out the many ways in which psychological factors affect the expression of physical disorder and vice-versa. Few doubt that stress makes many physical illnesses worse, at least as far as symptoms are concerned. There are also few physical illnesses in which the outcome is not made worse by psychological factors: depression after a heart attack, for example, has a worse e?ect on prognosis than even smoking. A little more problematic is the very popular belief that stress causes relapses of physical disorders, such as cancer; some studies have found this to be the case, others not.

However, calling a condition psychosomatic implies something more – the primacy of the psyche over the soma. Going back to the in?uential theories and practice of PSYCHOANALYSIS as expounded from the 1930s, many diseases have been proposed as the result of psychological factors.These have included PEPTIC ULCER, ULCERATIVE COLITIS, ASTHMA, PSORIASIS and others. In this view, much physical disorder is due to repressed or excessive emotions. Likewise it is also argued that whereas some people express psychological distress via psychological symptoms (such as anxiety, depression and so on), others develop physical symptoms instead – and that they are also at greater risk of physical disease.

The trouble with this view is that medical advances repeatedly show that it goes too far. Stress certainly causes physical symptoms – for example, DYSPEPSIA – but the belief that it caused peptic ulcers vanished with the discovery of the true cause: colonisation of the stomach by the bacterium, Helicobacter pylori. Of course, stress and social adversity affect the risk of many diseases. For example, the incidence of heart disease among UK government employees (civil servants) has been shown to be in?uenced by their social class and their degree of job satisfaction. But we do not know how this works. Some argue that social adversity and stress in?uence how the heart functions (‘He died of a broken heart’). Stress can also affect IMMUNITY but it cannot cause AIDS/HIV and we do not know if there is a link running from stress to abnormal immune function to actual illness.

We can say that psychological factors provoke physical symptoms, and often even explain how this can happen. For example, when you are anxious you produce more epinephrine (adrenaline), which gives rise to chest pain, ‘butter?ies in the stomach’ and PALPITATION. These symptoms are not ‘all in the mind’, even if the trigger is a psychological one. People who are depressed are more likely to experience nearly every physical symptom there is, but especially pain and fatigue. Taken as a whole, psychologically induced symptoms are an enormous burden on the NHS and probably responsible for more doctor visits and sickness absence than any other single cause. Also we can be con?dent that social adversity and stress powerfully in?uence the outcome of many illnesses; likewise, a vast range of unhealthy activities and behaviours such as smoking, excessive alcohol intake, excessive eating, and so on. But we must be careful not to assume that our emotions directly cause our illnesses.... psychosomatic diseases

Spleen, Diseases Of

In certain diseases associated with marked changes in the blood, such as LEUKAEMIA and MALARIA, the SPLEEN becomes chronically enlarged. In some of the acute infectious diseases, it becomes congested and acutely enlarged: for example, in typhoid fever (see ENTERIC FEVER), ANTHRAX and infectious MONONUCLEOSIS. Rupture of the spleen may occur, like rupture of other internal organs, in consequence of extreme violence – but in malarious countries, where many people have the spleen greatly enlarged and softened as the result of malaria, rupture of this organ occasionally occurs following even a light blow to the left side of the abdomen. The spleen, in consequence of its structure, bleeds excessively when torn, so that this accident is generally followed by collapse, signs of internal haemorrhage – and death if not dealt with promptly by operation.... spleen, diseases of

Testicle, Diseases Of

The SCROTUM may be affected by various skin diseases, particularly eczema (see DERMATITIS) or fungal infection. A HERNIA may pass into the scrotum. Defective development of the testicles may lead to their retention within the abdomen, a condition called undescended testicle.

Hydrocoele is a collection of ?uid distending one or both sides of the scrotum with ?uid. Treatment is by withdrawal of the ?uid using a sterile syringe and aspiration needle.

Hypogonadism Reduced activity of the testes or ovaries (male and female gonads). The result is impaired development of the secondary sexual characteristics (growth of the genitals, breast and adult hair distribution). The cause may be hereditary or the result of a disorder of the PITUITARY GLAND which produces GONADOTROPHINS that stimulate development of the testes and ovaries.

Varicocoele is distension of the veins of the spermatic cord, especially on the left side, the causes being similar to varicose veins elsewhere (see VEINS, DISEASES OF). The chief symptom is a painful dragging sensation in the testicle, especially after exertion. Wearing a support provides relief; rarely, an operation may be advisable. Low sperm-count may accompany a varicocele, in which case surgical removal may be advisable.

Orchitis or acute in?ammation may arise from CYSTITIS, stone in the bladder, and in?ammation in the urinary organs, especially GONORRHOEA. It may also follow MUMPS. Intense pain, swelling and redness occur; treatment consists of rest, support of the scrotum, analgesics as appropriate, and the administration of antibiotics if a de?nitive microorganism can be identi?ed. In some patients the condition may develop and form an ABSCESS.

Torsion or twisting of the spermatic cord is relatively common in adolescents. About half the cases occur in the early hours of the morning during sleep. Typically felt as pain of varying severity in the lower abdomen or scrotum, the testis becomes hard and swollen. Treatment consists of immediate undoing of the torsion by manipulation. If done within a few hours, no harm should ensue; however, this should be followed within six hours by surgical operation to ensure that the torsion has been relieved and to ?x the testes. Late surgical attention may result in ATROPHY of the testis.

Tuberculosis may occur in the testicle, especially when the bladder is already affected. Causing little pain, the infection is often far advanced before attracting attention. The condition generally responds well to treatment with a combination of antituberculous drugs (see also main entry for TUBERCULOSIS).

Tumours of the testes occur in around 600 males annually in the United Kingdom, and are the second most common form of malignant growth in young males. There are two types: SEMINOMA and TERATOMA. When adequately treated the survival rate for the former is 95 per cent, while that for the latter is 50 per cent.

Injuries A severe blow may lead to SHOCK and symptoms of collapse, usually relieved by rest in bed; however, a HAEMATOMA may develop.... testicle, diseases of

Rectum, Diseases Of

The following are described under their separate dictionary entries: FAECES; HAEMORRHOIDS; FISTULA; DIARRHOEA; CONSTIPATION.

Imperforate anus, or absence of the anus, may occur in newly born children, and the condition is relieved by operation.

Itching at the anal opening is common and can be troublesome. It may be due to slight abrasions, to piles, to the presence of threadworms (see ENTEROBIASIS), and/or to anal sex. The anal area should be bathed once or twice a day; clothing should be loose and smooth. Local application of soothing preparations containing mild astringents (bismuth subgallate, zinc oxide and hamamelis) and CORTICOSTEROIDS may provide symptomatic relief. Proprietary preparations contain lubricants, VASOCONSTRICTORS and mild ANTISEPTICS.

Pain on defaecation is commonly caused by a small ulcer or ?ssure, or by an engorged haemorrhoid (pile). Haemorrhoids may also cause an aching pain in the rectum. (See also PROCTALGIA.)

Abscess in the cellular tissue at the side of the rectum – known from its position as an ischio-rectal abscess – is fairly common and may produce a ?stula. Treatment is by ANTIBIOTICS and, if necessary, surgery to drain the abscess.

Prolapse or protrusion of the rectum is sometimes found in children, usually between the ages of six months and two years. This is generally a temporary disorder. Straining at defaecation by adults can cause the lining of the rectum to protrude outside the anus, resulting in discomfort, discharge and bleeding. Treatment of the underlying constipation is essential as well as local symptomatic measures (see above). Haemorrhoids sometimes prolapse. If a return to normal bowel habits with the production of soft faeces fails to restore the rectum to normal, surgery to remove the haemorrhoids may be necessary. If prolapse of the rectum recurs, despite a return to normal bowel habits, surgery may be required to rectify it.

Tumours of small size situated on the skin near the opening of the bowel, and consisting of nodules, tags of skin, or cauli?ower-like excrescences, are common, and may give rise to pain, itching and watery discharges. These are easily removed if necessary. Polypi (see POLYPUS) occasionally develop within the rectum, and may give rise to no pain, although they may cause frequent discharges of blood. Like polypi elsewhere, they may often be removed by a minor operation. (See also POLYPOSIS.)

Cancer of the rectum and colon is the commonest malignancy in the gastrointestinal tract: around 17,000 people a year die from these conditions in the United Kingdom. Rectal cancer is more common in men than in women; colonic cancer is more common in women. Rectal cancer is a disease of later life, seldom affecting young people, and its appearance is generally insidious. The tumour begins commonly in the mucous membrane, its structure resembling that of the glands with which the membrane is furnished, and it quickly in?ltrates the other coats of the intestine and then invades neighbouring organs. Secondary growths in most cases occur soon in the lymphatic glands within the abdomen and in the liver. The symptoms appear gradually and consist of diarrhoea, alternating with attacks of constipation, and, later on, discharges of blood or blood-stained ?uid from the bowels, together with weight loss and weakness. A growth can be well advanced before it causes much disturbance. Treatment is surgical and usually this consists of removal of the whole of the rectum and the distal two-thirds of the sigmoid colon, and the establishment of a COLOSTOMY. Depending upon the extent of the tumour, approximately 50 per cent of the patients who have this operation are alive and well after ?ve years. In some cases in which the growth occurs in the upper part of the rectum, it is now possible to remove the growth and preserve the anus so that the patient is saved the discomfort of having a colostomy. RADIOTHERAPY and CHEMOTHERAPY may also be necessary.... rectum, diseases of

Sexually Transmitted Diseases (stds)

Sexually transmitted diseases – traditionally called venereal diseases – are infections transmitted by sexual intercourse (heterosexual and homosexual). In the United Kingdom they are treated in genito-urinary medicine (GUM) clinics. The incidences of these diseases are more common among people who have several sexual partners, as STDs are very infectious; some of the major STDs, particularly AIDS/HIV, are also transmitted by blood and so can result from needle-sharing by drug addicts, or by TRANSFUSION. The ‘traditional’ STDs – SYPHILIS, GONORRHOEA and CHANCROID – now comprise only 10 per cent of all such diseases treated in STD clinics: these clinics also treat patients with CHLAMYDIA, TRICHOMONIASIS, HERPES GENITALIS, MOLLUSCUM CONTAGIOSUM and genital WARTS. SCABIES and pubic lice (see PEDICULOSIS – Pediculus pubis) can also be transmitted by sexual intercourse, and HEPATITIS B is also recognised as an STD.

The incidence of STDs rose sharply during World War II but the advent of PENICILLIN and subsequent antibiotics meant that syphilis and gonorrhoea could be treated e?ectively. The arrival of oral contraception and more tolerant public attitudes to sexual activities resulted in an increase in the incidence of sexually transmitted infections. The diagnosis of NONSPECIFIC URETHRITIS (NSU), once given to many patients whose symptoms were not due to the traditional recognised infections, was in the 1970s realised to be wrong, as the condition was proved to be the result of infection by chlamydia.

Most STDs are treatable, but herpes is an infection that could become chronic, while hepatitis B and, of course, AIDS/HIV are potentially fatal – although treatment of HIV is now proving more e?ective. As well as the treatment and subsequent monitoring of patients with STDs, one of the important functions of clinics has been the tracing, treatment and follow-up of sexual contacts of infected individuals, a procedure that is conducted con?dentially.

Apart from AIDS/HIV, the incidence of STDs fell during the 1980s; however in some countries the agents causing syphilis and gonorrhoea began to develop resistance to antibiotics, which showed the continued importance of practising safe sex – in particular by restricting the number of sexual partners and ensuring the regular use of condoms. In the United Kingdom the rates per million of the male population infected by syphilis rose from 8.8 in 1991 to 9.7 in 1999; in females the ?gures were 4.0 to 4.5, respectively. For gonorrhoea, the ?gures for men were 399.4 in 1991 and 385 in 1999, with women also showing a reduction, from

216.5 to 171.3. In 1991, 552.6 per million of men had chlamydia, a ?gure which rose to

829.5 in 1999; for women in the same period the incidence also rose, from 622.5 to 1,077.1 per million. For genital herpes simplex virus, the infection rate for men fell from 236.6 per million to 227.7, whereas the ?gures for women showed a rise, 258.5 to 357. The incidence of AIDS/HIV is given under the relevant entry. (These ?gures are based on information in United Kingdom Health Statistics, 2001 edition, UKHSI, published by the O?ce of National Statistics.)... sexually transmitted diseases (stds)

Urethra, Diseases Of And Injury To

Trauma Injury to the urethra is often the result of severe trauma to the pelvis – for example, in a car accident or as the result of a fall. Trauma can also result from catheter insertion (see CATHETERS) or the insertion of foreign bodies into the urethra. The signs are the inability to pass urine, and blood at the exit of the urethra. The major complication of trauma is the development of a urethral stricture (see below).

Urethritis is in?ammation of the urethra from infection.

Causes The sexually transmitted disease GONORRHOEA affects the urethra, mainly in men, and causes severe in?ammation and urethritis. Non-speci?c urethritis (NSU) is an in?ammation of the urethra caused by one of many di?erent micro-organisms including BACTERIA, YEAST and CHLAMYDIA.

Symptoms The classic signs and symptoms are a urethral discharge associated with urethral pain, particularly on micturition (passing urine), and DYSURIA.

Treatment This involves taking urethral swabs, culturing the causative organism and treating it with the appropriate antibiotic. The complications of urethritis include stricture formation.

Stricture This is an abrupt narrowing of the urethra at one or more places. Strictures can be a result of trauma or infection or a congenital abnormality from birth. Rarely, tumours can cause strictures.

Symptoms The usual presenting complaint is one of a slow urinary stream. Other symptoms include hesitancy of micturition, variable stream and terminal dribbling. Measurement of the urine ?ow rate may help in the diagnosis, but often strictures are detected during cystoscopy (see CYSTOSCOPE).

Treatment The traditional treatment was the periodic dilation of the strictures with ‘sounds’

– solid metal rods passed into the urethra. However, a more permanent solution is achieved by cutting the stricture with an endoscopic knife (optical urethrotomy). For more complicated long or multiple strictures, an open operation (urethroplasty) is required.... urethra, diseases of and injury to

Skin, Diseases Of

They may be local to the SKIN, or a manifestation of systemic disorders – inherited or acquired. Some major types are described below.

Others appear under their appropriate alphabetical headings: ACNE; ALBINISM; ALOPECIA; ALOPECIA AREATA; APHTHOUS ULCER; BASAL CELL CARCINOMA; BOILS (FURUNCULOSIS); BOWEN’S DISEASE; CALLOSITIES; CANDIDA; CHEILOSIS; CHEIRAPOMPHOLYX; DANDRUFF; DERMATOFIBROMA; DERMATOMYOSITIS; DERMATOPHYTES; DERMOGRAPHISM; ECTHYMA; ERYSIPELAS; ERYTHEMA; ERYTHRASMA; ERYTHRODERMA; ESCHAR; EXANTHEM; FUNGAL AND YEAST INFECTIONS; HAND, FOOT AND MOUTH DISEASE; HERPES GENITALIS; HERPES SIMPLEX; HERPES ZOSTER; IMPETIGO; INTERTRIGO; KELOID; KERATOSIS; LARVA MIGRANS; LICHEN; LUPUS; MADURA FOOT; MELANOMA; MILIARIA; MOLLUSCUM CONTAGIOSUM; MOLE; MYCOSIS FUNGOIDES; NAEVUS; ORF; PEDICULOSIS; PEMPHIGUS; PHOTOCHEMOTHERAPY; PHOTODERMATOSES; PITYRIASIS; PORPHYRIAS; PRURITUS; PSORIASIS; RINGWORM; ROSACEA; SARCOIDOSIS; SCABIES; SCLERODERMA; URTICARIA; VITILIGO; WARTS; XANTHOMATA.

Skin cancer Primary cancer is common and chronic exposure to ultraviolet light is the most important cause. BASAL CELL CARCINOMA is the most common form; squamous cell carcinoma is less common and presents as a growing, usually painless nodule which may ulcerate. Squamous cancer may spread to regional lymph glands and metastasise, unlike basal cell cancer. Occupational exposure to chemical carcinogens may cause squamous carcinoma – for example, cancer from pitch warts or the scrotal carcinoma of chimney sweeps exposed to coal dust in earlier centuries. Squamous carcinoma of the lip is associated with clay-pipe smoking.

Cancer may arise from the population of melanocytes of the skin (see MELANOCYTE; MELANOMA).

Apart from these three most frequent forms of skin cancer, various forms of cancer can arise from cells of the dermis, of which LYMPHOMA is the most important (see also MYCOSIS FUNGOIDES).

Lastly, secondary deposits from internal cancer, particularly from the breast, may metastasise to the skin.

Dermatitis and eczema These are broadly synonymous, and the terms are frequently interchangeable. Eczema is a pattern of in?ammation with many potential causes. Dermatitis is commonly used to suggest an eczema caused by external factors; it is a common pattern of in?ammation of the skin characterised by redness and swelling, vesiculation (see VESICLE), and scaling with intense itching and often exudation (weeping). Fissuring, thickening (licheni?cation – see LICHEN) and secondary bacterial infection may follow. Dermatitis can affect any part of the body. It may be genetically detemined or due to other ‘internal’ factors, such as venous HYPERTENSION in a leg, or stress. Often it is ‘external’ in origin – due to strong irritants or chemical allergens. (See also ALLERGY; ALLERGEN.) ATOPIC DERMATITIS is genetic in origin and usually begins in infancy. It may persist for years, and ASTHMA, allergic RHINITIS and conjunctivitis (see under EYE, DISORDERS OF) – ‘hay fever’ – may be associated. Atopic children tend to have multiple allergies, especially to inhaled allergens such as house-dust mite, cat and dog dander and pollens. Allergy to foods is less common but potentially more dangerous, especially if to nuts, when it can cause acute URTICARIA or even ANAPHYLAXIS. Atopic subjects are particularly prone to persistent and multiple verrucae (see WARTS) and mollusca (see MOLLUSCUM CONTAGIOSUM) and to severe HERPES SIMPLEX infections. (See also ATOPY.)

EXFOLIATE DERMATITIS (PITYRIASIS RUBRA)

Generalised exfoliation and scaling of the skin, commonly with ERYTHEMA. Drugs may cause it, or the disorder may be linked with other skin diseases such as benign dermatoses and lupus erythematosus (see under LUPUS). SUMMER POMPHOLYX is an acute vesicular eczema of the palms and soles recurring every summer. Inhaled allergens are a frequent cause. VENOUS (STASIS) DERMATITIS begins on a lower calf, often in association with PURPURA, swelling and sometimes ulceration. Chronic venous hypertension in the leg, consequent on valvular incompetence in the deep leg veins owing to previous deep vein thrombosis (see VEINS, DISEASES OF), is the usual cause. NEURODERMATITIS A pattern of well-de?ned plaques of licheni?ed eczema particularly seen on the neck, ulnar forearms or sides of the calves in subjects under emotional stress. IRRITANT CONTACT DERMATITIS Most often seen in an industrial setting (occupational dermatitis), it is due to damage by strong chemicals such as cutting oils, cement, detergents and solvents. In almost all cases the hands are most severely affected. ALLERGIC CONTACT DERMATITIS, in contrast, can affect any part of the body depending on the cause – for example, the face (cosmetics), hands (plants, occupational allergens) or soles (rubber boots). Particularly common allergens include metals (nickel and chromate), rubber addititives, and adhesives (epoxy resins).

Treatment Avoidance of irritants and contact allergens, liberal use of EMOLLIENTS, and topical application of corticosteroid creams and ointments (see CORTICOSTEROIDS) are central.... skin, diseases of

Spine And Spinal Cord, Diseases And Injuries Of

Scoliosis A condition where the spine is curved to one side (the spine is normally straight when seen from behind). The deformity may be mobile and reversible, or ?xed; if ?xed it is accompanied by vertebral rotation and does not disappear with changes in posture. Fixed scoliosis is idiopathic (of unknown cause) in 65–80 per cent of cases. There are three main types: the infantile type occurs in boys under three and in 90 per cent of cases resolves spontaneously; the juvenile type affects 4–9 year olds and tends to be progressive. The most common type is adolescent idiopathic scoliosis; girls are affected in 90 per cent of cases and the incidence is 4 per cent. Treatment may be conservative with a ?xed brace, or surgical fusion may be needed if the curve is greater than 45 degrees. Scoliosis can occur as a congenital condition and in neuromuscular diseases where there is muscle imbalance, such as in FRIEDREICH’S ATAXIA.

Kyphosis is a backward curvature of the spine causing a hump back. It may be postural and reversible in obese people and tall adolescent girls who stoop, but it may also be ?xed. Scheuermann’s disease is the term applied to adolescent kyphosis. It is more common in girls. Senile kyphosis occurs in elderly people who probably have osteoporosis (bone weakening) and vertebral collapse.

Disc degeneration is a normal consequence of AGEING. The disc loses its resiliance and becomes unable to withstand pressure. Rupture (prolapse) of the disc may occur with physical stress. The disc between the fourth and ?fth lumbar vertebrae is most commonly involved. The jelly-like central nucleus pulposus is usually pushed out backwards, forcing the annulus ?brosus to put pressure on the nerves as they leave the spinal canal. (See PROLAPSED INTERVERTEBRAL DISC.)

Ankylosing spondylitis is an arthritic disorder of the spine in young adults, mostly men. It is a familial condition which starts with lumbar pain and sti?ness which progresses to involve the whole spine. The discs and ligaments are replaced by ?brous tissue, making the spine rigid. Treatment is physiotherapy and anti-in?ammatory drugs to try to keep the spine supple for as long as possible.

A National Association for Ankylosing Spondylitis has been formed which is open to those with the disease, their families, friends and doctors.

Spondylosis is a term which covers disc degeneration and joint degeneration in the back. OSTEOARTHRITIS is usually implicated. Pain is commonly felt in the neck and lumbar regions and in these areas the joints may become unstable. This may put pressure on the nerves leaving the spinal canal, and in the lumbar region, pain is generally felt in the distribution of the sciatic nerve – down the back of the leg. In the neck the pain may be felt down the arm. Treatment is physiotherapy; often a neck collar or lumbar support helps. Rarely surgery is needed to remove the pressure from the nerves.

Spondylolisthesis means that the spine is shifted forward. This is nearly always in the lower lumbar region and may be familial, or due to degeneration in the joints. Pressure may be put on the cauda equina. The usual complaint is of pain after exercise. Treatment is bed rest in a bad attack with surgery indicated only if there are worrying signs of cord compression.

Spinal stenosis is due to a narrowing of the spinal canal which means that the nerves become squashed together. This causes numbness with pins and needles (paraesthia) in the legs. COMPUTED TOMOGRAPHY and nuclear magnetic resonance imaging scans can show the amount of cord compression. If improving posture does not help, surgical decompression may be needed.

Whiplash injuries occur to the neck, usually as the result of a car accident when the head and neck are thrown backwards and then forwards rapidly. This causes pain and sti?ness in the neck; the arm and shoulder may feel numb. Often a support collar relieves the pain but recovery commonly takes between 18 months to three years.

Transection of the cord occurs usually as a result of trauma when the vertebral column protecting the spinal cord is fractured and becomes unstable. The cord may be concussed or it may have become sheared by the trauma and not recover (transected). Spinal concussion usually recovers after 12 hours. If the cord is transected the patient remains paralysed. (See PARALYSIS.)... spine and spinal cord, diseases and injuries of

Demyelinating Diseases

Disorders that destroy myelin, a fatty substance which forms a sheath round nerve fibres and appears in the central nervous system. A typical example is multiple sclerosis.

Essential fatty acids have an important role in the function of the nervous system, being closely related to the fatty (myelin) sheath and cell membranes. Disturbance in their metabolism may result in nerve disorder. Thus, vegetable oils of Soya, corn, safflower and sunflower should replace animal fats and dairy products.

Symptoms. Numb, prickling, tickling sensation on the skin, paralysis, incoordination, physical weakness and visual complaints.

Treatment. Indeterminate diagnosis.

Tablets/capsules. Prickly Ash, Black Cohosh, Ginseng, Ginkgo.

Powders, Liquid Extracts, Tinctures. Formula. Equal parts: Black Cohosh, Prickly Ash, Ginseng. Doses. Powders: two 00 capsules or one-third teaspoon, (500mg). Liquid Extracts: 1 teaspoon. Tinctures: 2 teaspoons. In water, honey or fruit juice.

Evening Primrose oil capsules or tablets: two 500mg thrice daily.

Aromatherapy. Rosemary spinal rub: 6 drops Oil Rosemary in 2 teaspoons Almond oil.

Diet. High protein, low fat, oily fish or 2 teaspoons Cod Liver oil daily. Gluten-free diet. Cholesterol- free – avoid milk, meat fat and dairy products. Avoid coffee and other caffeine stimulants. Dandelion coffee.

Supplements. B-complex, B3, B6, B12, C, E. Dolomite, Manganese, Zinc. ... demyelinating diseases

Urinary Bladder, Diseases Of

Diseases of the URINARY BLADDER are diagnosed by the patient’s symptoms and signs, examination of the URINE, and using investigations such as X-RAYS and ULTRASOUND scans. The interior of the bladder can be examined using a cystoscope, which is a ?breoptic endoscope (see FIBREOPTIC ENDOSCOPY) that is passed into the bladder via the URETHRA.

Cystitis Most cases of cystitis are caused by bacteria which have spread from the bowel, especially Escherichia coli, and entered the bladder via the urethra. Females are more prone to cystitis than are males, owing to their shorter urethra which allows easier entry for bacteria. Chronic or recurrent cystitis may result in infection spreading up the ureter to the kidney (see KIDNEY, DISEASES OF).

Symptoms Typically there is frequency and urgency of MICTURITION, with stinging and burning on passing urine (dysuria), which is often smelly or bloodstained. In severe infection patients develop fever and rigors, or loin pain. Before starting treatment a urine sample should be obtained for laboratory testing, including identi?cation of the invading bacteria.

Treatment This includes an increased ?uid intake, ANALGESICS, doses of potassium citrate to make the urine alkaline to discourage bacterial growth, and an appropriate course of ANTIBIOTICS once a urine sample has been ana-lysed in the laboratory to con?rm the diagnosis and determine what antibiotics the causative organism is likely to respond to.

Stone or calculus The usual reason for the formation of a bladder stone is an obstruction to the bladder out?ow, which results in stagnant residual urine – ideal conditions for the crystallisation of the chemicals that form stones – or from long-term indwelling CATHETERS which weaken the natural mechanical protection against bacterial entry and, by bruising the lining tissues, encourage infection.

Symptoms The classic symptom is a stoppage in the ?ow of urine during urination, associated with severe pain and the passage of blood.

Treatment This involves surgical removal of the stone either endoscopically (litholapaxy); by passing a cystoscope into the bladder via the urethra and breaking the stone; or by LITHOTRIPSY in which the stone (or stones) is destroyed by applying ultrasonic shock waves. If the stone cannot be destroyed by these methods, the bladder is opened and the stone removed (cystolithotomy).

Cancer Cancer of the bladder accounts for 7 per cent of all cancers in men and 2·5 per cent in women. The incidence increases with age, with smoking and with exposure to the industrial chemicals, beta-napththylamine and benzidine. In 2003, 2,884 men and 1,507 women died of bladder cancer in England and Wales.

Symptoms The classical presenting symptom of a bladder cancer is the painless passing of blood in the urine – haematuria. All patients with haematuria must be investigated with an X-ray of their kidneys, an INTRAVENOUS PYELOGRAM (UROGRAM) and a cystoscopy.

Treatment Super?cial bladder tumours on the lining of the bladder can be treated by local removal via the cystoscope using DIATHERMY (cystodiathermy). Invasive cancers into the bladder muscle are usually treated with RADIOTHERAPY, systemic CHEMOTHERAPY or surgical removal of the bladder (cystectomy). Local chemotherapy may be useful in some patients with multiple small tumours.... urinary bladder, diseases of

Asbestos-related Diseases

A variety of diseases caused by inhalation of asbestos fibres. Asbestos is a fibrous mineral formerly used as a heat- and fire-resistant insulating material. There are 3 main types of asbestos fibre: white, which is widely used; blue; and brown, the most dangerous. The use of all types is now carefully controlled.

In asbestosis, widespread fine scarring occurs in the lungs. The disease causes breathlessness and a dry cough, eventually leading to severe disability and death. It develops mostly in industrial workers who have been heavily exposed to asbestos. The period from initial exposure to development of the disease is usually at least 20 years. Diagnosis is by chest X-ray. Asbestosis increases the risk of lung cancer.

Mesothelioma is a cancerous tumour of the pleura (the membrane surrounding the lungs) or the peritoneum (the membrane lining the abdominal cavity). In the pleura, mesotheliomas cause pain and breathlessness; in the peritoneum they cause enlargement of the abdomen and intestinal obstruction. The condition cannot be treated and usually leads to death within 1 or 2 years. The average interval between initial exposure to asbestos and death is 20–30 years. Mesothelioma affects people who have worked with blue or brown asbestos.

In diffuse pleural thickening, the outer and inner layers of the pleura become thickened, and excess fluid may accumulate in the cavity between them.

This combination restricts the ability of the lungs to expand, resulting in shortness of breath.

The condition may develop even after short exposure to asbestos.... asbestos-related diseases

Veins, Diseases Of

Veins are the blood vessels that convey blood back from the tissues towards the heart. Two common conditions that affect them are THROMBOSIS and varicosities (see below).

Varicose veins are dilated tortuous veins occurring in about 15 per cent of adults – women more than men. They most commonly occur in the legs but may also occur in the anal canal (HAEMORRHOIDS) and in the oesophagus (due to liver disease).

Normally blood ?ows from the subcutaneous tissues to the super?cial veins which drain via perforating veins into the deep veins of the leg. This ?ow, back towards the heart, is aided by valves within the veins. When these valves fail, increased pressure is exerted on the blood vessels leading to dilatations known as varicose veins.

Treatment is needed to prevent complications such as ulceration and bleeding, or for

cosmetic purposes. Treatment alternatives include injection with sclerosing agents to obliterate the lumen of the veins (sclerotherapy), or surgery; in the elderly or un?t, an elastic stocking may su?ce. One operation is the Trendelenburg operation in which the saphenous vein is disconnected from the femoral vein and individual varicose veins are avulsed. (See also VASCULITIS.)

Thrombosis Thrombosis occurs when blood, which is normally a liquid, clots within the vein to form a semisolid thrombus (clot). This occurs through a combination of reduced blood ?ow and hypercoagulability (a reduced threshold for clotting). The most common site for this to occur is in the deep veins of the leg, where it is known as a deep-vein thrombosis (DVT).

Predisposing factors include immobility (leading to reduced blood ?ow), such as during long journeys (e.g. plane ?ights) where there is little opportunity to stretch one’s legs; surgery (leading to temporary post-operative immobility and hypercoagulability of blood); oestrogen administration (low-dose oestrogen oral contraceptives carry a very low relative risk); and several medical illnesses such as heart failure, stroke and malignancy.

Deep-vein thrombosis presents as a tender, warm, red swelling of the calf. Diagnosis may be con?rmed by venogram (an X-ray taken following injection of contrast medium into the foot veins) or by ultrasound scanning looking for ?ow within the veins.

Prevention is important. This is why patients are mobilised and/or given leg exercises very soon after an operation, even major surgery. People should avoid sitting for long periods, particularly if the edge of the seat is hard, thus impeding venous return from the legs. Car drivers should stop regularly on a long journey and walk around; airline travellers should, where possible, walk round the aisle(s) and also exercise and massage their leg muscles, as well as drinking ample non-alcoholic ?uids.

Diagnosis and treatment are important because there is a risk that the clotted blood within the vein becomes dislodged and travels up the venous system to become lodged in the pulmonary arteries. This is known as PULMONARY EMBOLISM.

Treatment is directed at thinning the blood with ANTICOAGULANTS, initially with heparin and subsequently with WARFARIN for a period of time while the clot resolves.

Blocked super?cial veins are described as super?cial thrombophlebitis, which produces in?ammation over the vein. It responds to antiin?ammatory analgesics. Occasionally heparin and ANTIBIOTICS are required to treat associated thrombosis and infection.... veins, diseases of

Cats, Diseases From

Various parasites and infectious organisms can spread from cats to humans. The most serious disease is rabies. Cat-scratch fever is an uncommon illness caused by infection with the bacterium ROCHALIMAEA HENDELAE following a cat scratch or bite. Cats commonly carry the protozoan TOXOPLASMA GONDII, which causes toxoplasmosis.

Infection, usually from contact with cat’s faeces, is not generally serious but has serious consequences if a woman is infected during pregnancy.

Cat faeces may also carry eggs of the cat roundworm, a possible cause of toxocariasis.

Rarely, a larva from an ingested roundworm egg migrates to and lodges in an eye, causing deterioration of vision or even blindness.

Children who have been playing in sand or soil contaminated by cat faeces are most commonly affected.

Other cat-related disorders in humans include tinea (ringworm), fungal infections of the skin, bites from cat fleas, and allergic reactions to dander that may cause asthma or urticaria.

Diseases from cats can be avoided by good hygiene, veterinary care for animals that are ill, and regular worming and flea treatment of cats.... cats, diseases from

Dogs, Diseases From

Infectious or parasitic diseases that are acquired from contact with dogs. They may be caused by viruses, bacteria, fungi, protozoa, worms, insects, or mites living in or on a dog. Many parasites that live on dogs can be transferred to humans. The most serious disease from dogs is rabies. The is free of rabies, but travellers to countries in which rabies exists should treat any bite with suspicion. Dog bites can cause serious bleeding and shock and may become infected. Toxocariasis and hydatid disease are potentially serious diseases caused by the ingestion of worm eggs from dogs. In the tropics, walking barefoot on soil that is contaminated with dog faeces can lead to dog hookworm infestation.

Bites from dog fleas are an occasional nuisance. Ticks and mites from dogs, including a canine version of the scabies mite, are other common problems. The fungi that cause tinea infections in dogs can be caught by humans.

Some people become allergic to animal dander (tiny scales from fur or skin). They may, for example, have asthma or urticaria when a dog is in the house. (See also zoonoses.)... dogs, diseases from

Rats, Diseases From

Rats are rodents that live close to human habitation. They damage and contaminate crops and food stores and can spread disease. The organisms responsible for plague and a type of typhus are transmitted to humans by the bites of rat fleas. Leptospirosis is caused by contact with anything contaminated by rat’s urine.

Rat-bite fever is a rare infection transmitted directly by a rat bite. There are 2 types of this infection, caused by different bacteria. The symptoms include inflammation at the site of the bite and in nearby lymph nodes and vessels, bouts of fever, a rash, and, in one type, painful joint inflammation. Treatment for both types is with antibiotic drugs.

Rabies virus can be transmitted by the bites of infected rats. Lassa fever, also a viral disease, may be contracted from the urine of rats in West Africa. Rats also carry the viral infection lymphocytic chorio-meningitis, as well as the bacterial infection tularaemia.... rats, diseases from

International Classification Of Diseases

(ICD) a list of all known diseases and syndromes, including mental and behavioural disorders, published by the *World Health Organization every ten years (approximately). Over the years the classification has moved from being disease-orientated to include a wider framework of illness and other health problems. The version in current use, ICD-10, was published in 1992 and employs alphanumeric coding. It is used in many countries as the principal means of classifying both mortality and morbidity experience and allows comparison of morbidity and mortality rates nationally and internationally. The clinical utility of the ICD is a matter of some controversy, especially in the field of psychiatry. ICD-11 was published in June 2018 and is intended to come into use from 2022. It includes about 55,000 codes for injuries, diseases, and causes of death, which is three times more than its predecessor. It also differs substantially from ICD-10 as each disease entry includes descriptions and guidance as to what is covered by the term, rather than the term alone. For the first time it includes specific sections on sexual health and traditional medicine. A parallel list, the International Classification of Functioning, Disabilities and Health (ICF), has also been compiled and is being used alongside the ICD. See also handicap.

The standard international classification for statistical, administrative, and epidemiological purposes, as supplied by the World Health Organization

The WHO framework for measuring health and disability in individuals and populations... international classification of diseases


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