Prone to infection by parasites and pathogens. A person or anima l presumably not possessing sufficient resistance against a particular pathogenic agent and for that reason liable to contact a disease if or when exposed to the disease agent.
Frostbite can affect any part of the body, but the extremities (the nose, ears, fingers, and toes) are most susceptible.
The first symptoms of frostbite are a pins-andneedles sensation, followed by complete numbness.
The skin appears white, cold, and hard and then becomes red and swollen.
If damage is restricted to the skin and immediately underlying tissues, recovery may be complete.
If blood vessels are affected, gangrene may follow.
In such cases, amputation of the affected part may be necessary.... frostbite
Fair-skinned people are most susceptible.
The affected skin turns red and tender and may become blistered.
The dead skin cells are later shed by peeling.
Calamine lotion soothes the burned skin.
Analgesic drugs may be taken to relieve discomfort.
A high protection factor sunscreen helps to prevent sunburn.
Severe sunburn in childhood increases the risk of skin cancer in later life.... sunburn
Both HIV-1 and HIV-2 are predominantly sexually transmitted and both are associated with secondary opportunistic infections. However, HIV-2 seems to result in slower damage to the immune system. HIV-1 is known to mutate rapidly and has given rise to other subtypes.
HIV is thought to have occurred in humans in the 1950s, but whether or not it infected humans from another primate species is uncertain. It became widespread in the 1970s but its latency in causing symptoms meant that the epidemic was not noticed until the following decade. Although it is a sexually transmitted disease, it can also be transmitted by intravenous drug use (through sharing an infected needle), blood transfusions with infected blood (hence the importance of e?ective national blood-screening programmes), organ donation, and occupationally (see health-care workers, below). Babies born of HIV-positive mothers can be infected before or during birth, or through breast feeding.
Although HIV is most likely to occur in blood, semen or vaginal ?uid, it has been found in saliva and tears (but not sweat); however, there is no evidence that the virus can be transmitted from these two body ?uids. There is also no evidence that HIV can be transmitted by biting insects (such as mosquitoes). HIV does not survive well in the environment and is rapidly destroyed through drying.
Prevalence At the end of 2003 an estimated 42 million people globally were infected with HIV – up from 40 million two years earlier. About one-third of those with HIV/AIDS are aged 15–24 and most are unaware that they are carrying the virus. During 2003 it is estimated that 5 million adults and children worldwide were newly infected with HIV, and that 3 million adults and children died. In Africa in 2003,
3.4 million people were newly infected and 2.3 million died, with more than 28 million carrying the virus. HIV/AIDS was the leading cause of death in sub-Saharan Africa where over half of the infections were in women and 90 per cent of cases resulted from heterosexual sex. In some southern African countries, one in three pregnant women had HIV.
In Asia and the Paci?c there were 1.2 million new infections and 435,000 deaths. The area with the fastest-growing epidemic is Eastern Europe, especially the Russian Federation where in 2002 around a million people had HIV and there were an estimated 250,000 new infections, with intravenous drug use a key contributor to this ?gure. Seventy-?ve per cent of cases occurred in men, with male-to-male sexual transmission an important cause of infection, though heterosexual activity is a rising cause of infection.
At the end of 2002 the UK had an estimated 55,900 HIV-infected adults aged between 15 and 59. More than 3,600 individuals were newly diagnosed with the infection in 2000, the highest annual ?gure since the epidemic started
– in 1998 the ?gure was 2,817 and in 1999 just over 3,000 (Department of Health and Communicable Disease Surveillance Centre). The incidence of AIDS in the UK has declined sharply since the introduction of highly active antiretroviral therapy (HAART) and HIV-related deaths have also fallen: in 2002 there were 777 reported new AIDS cases and 395 deaths, compared with 1,769 and 1,719 respectively in 1995. (Sources: UNAIDS and WHO, AIDS Epidemic Update, December 2001; Public Health Laboratory Services AIDS and STD Centre Communicable Disease Surveillance and Scottish Centre for Infection and Environmental Health, Quarterly Surveillance Tables.)
Poverty is strongly linked to the spread of AIDS, for various reasons including lack of health education; lack of e?ective public-health awareness; women having little control over sexual behaviour and contraception; and, by comparison with the developed world, little or no access to antiretroviral drugs.
Pathogenesis The cellular target of HIV infection is a subset of white blood cells called T-lymphocytes (see LYMPHOCYTE) which carry the CD4 surface receptor. These so-called ‘helper T-cells’ are vital to the function of cell-mediated immunity. Infection of these cells leads to their destruction (HIV replicates at an enormous rate – 109) and over the course of several years the body is unable to generate suf?cient new cells to keep pace. This leads to progressive destruction of the body’s immune capabilities, evidenced clinically by the development of opportunistic infection and unusual tumours.
Monitoring of clinical progression It is possible to measure the number of viral particles present in the plasma. This gives an accurate guide to the likely progression rate, which will be slow in those individuals with fewer than 10,000 particles per ml of plasma but progressively more rapid above this ?gure. The main clinical monitoring of the immune system is through the numbers of CD4 lymphocytes in the blood. The normal count is around 850 cells per ml and, without treatment, eventual progression to AIDS is likely in those individuals whose CD4 count falls below 500 per ml. Opportunistic infections occur most frequently when the count falls below 200 per ml: most such infections are treatable, and death is only likely when the CD4 count falls below 50 cells per ml when infection is developed with organisms that are di?cult to treat because of their low intrinsic virulence.
Simple, cheap and highly accurate tests are available to detect HIV antibodies in the serum. These normally occur within three months of infection and remain the cornerstone of the diagnosis.
Clinical features Most infected individuals have a viral illness some three weeks after contact with HIV. The clinical features are often non-speci?c and remain undiagnosed but include a ?ne red rash, large lymph nodes, an in?uenza-like illness, cerebral involvement and sometimes the development of opportunistic infections. The antibody test may be negative at this stage but there are usually high levels of virus particles in the blood. The antibody test is virtually always positive within three months of infection. HIV infection is often subsequently asymptomatic for a period of ten years or more, although in most patients progressive immune destruction is occurring during this time and a variety of minor opportunistic infections such as HERPES ZOSTER or oral thrush (see CANDIDA) do occur. In addition, generalised LYMPHADENOPATHY is present in a third of patients and some suffer from severe malaise, weight loss, night sweats, mild fever, ANAEMIA or easy bruising due to THROMBOCYTOPENIA.
The presentation of opportunistic infection is highly variable but usually involves either the CENTRAL NERVOUS SYSTEM, the gastrointestinal tract or the LUNGS. Patients may present with a sudden onset of a neurological de?cit or EPILEPSY due to a sudden onset of a STROKE-like syndrome, or epilepsy due to a space-occupying lesion in the brain – most commonly TOXOPLASMOSIS. In late disease, HIV infection of the central nervous system itself may produce progressive memory loss, impaired concentration and mental slowness called AIDS DEMENTIA. A wide variety of opportunistic PROTOZOA or viruses produces DYSPHAGIA, DIARRHOEA and wasting. In the respiratory system the commonest opportunistic infection associated with AIDS, pneumonia, produces severe shortness of breath and sometimes CYANOSIS, usually with a striking lack of clinical signs in the chest.
In very late HIV infection, when the CD4 count has fallen below 50 cells per ml, infection with CYTOMEGALOVIRUS may produce progressive retinal necrosis (see EYE, DISORDERS OF) which will lead to blindness if untreated, as well as a variety of gastrointestinal symptoms. At this stage, infection with atypical mycobacteria is also common, producing severe anaemia, wasting and fevers. The commonest tumour associated with HIV is Kaposi’s sarcoma which produces purplish skin lesions. This and nonHodgkin’s lymphoma (see LYMPHOMA), which is a hundred times more frequent among HIV-positive individuals than in the general population, are likely to be associated with or caused by opportunistic viral infections.
Prevention There is, as yet, no vaccine to prevent HIV infection. Vaccine development has been hampered
by the large number of new HIV strains generated through frequent mutation and recombination.
because HIV can be transmitted as free virus and in infected cells.
because HIV infects helper T-cells – the very cells involved in the immune response. There are, however, numerous research pro
grammes underway to develop vaccines that are either prophylactic or therapeutic. Vaccine-development strategies have included: recombinant-vector vaccines, in which a live bacterium or virus is genetically modi?ed to carry one or more of the HIV genes; subunit vaccines, consisting of small regions of the HIV genome designed to induce an immune response without infection; modi?ed live HIV, which has had its disease-promoting genes removed; and DNA vaccines – small loops of DNA (plasmids) containing viral genes – that make the host cells produce non-infectious viral proteins which, in turn, trigger an immune response and prime the immune system against future infection with real virus.
In the absence of an e?ective vaccine, preventing exposure remains the chief strategy in reducing the spread of HIV. Used properly, condoms are an extremely e?ective method of preventing exposure to HIV during sexual intercourse and remain the most important public-health approach to countering the further acceleration of the AIDS epidemic. The spermicide nonoxynol-9, which is often included with condoms, is known to kill HIV in vitro; however, its e?ectiveness in preventing HIV infection during intercourse is not known.
Public-health strategies must be focused on avoiding high-risk behaviour and, particularly in developing countries, empowering women to have more control over their lives, both economically and socially. In many of the poorer regions of the world, women are economically dependent on men and refusing sex, or insisting on condom use, even when they know their partners are HIV positive, is not a straightforward option. Poverty also forces many women into the sex industry where they are at greater risk of infection.
Cultural problems in gaining acceptance for universal condom-use by men in some developing countries suggests that other preventive strategies should also be considered. Microbicides used as vaginal sprays or ‘chemical condoms’ have the potential to give women more direct control over their exposure risk, and research is underway to develop suitable products.
Epidemiological studies suggest that male circumcision may o?er some protection against HIV infection, although more research is needed before this can be an established public-health strategy. Globally, about 70 per cent of infected men have acquired the virus through unprotected vaginal sex; in these men, infection is likely to have occurred through the penis with the mucosal epithelia of the inner surface of the foreskin and the frenulum considered the most likely sites for infection. It is suggested that in circumcised men, the glans may become keratinised and thus less likely to facilitate infection. Circumcision may also reduce the risk of lesions caused by other sexually transmitted disease.
Treatment AIDS/HIV treatment can be categorised as speci?c therapies for the individual opportunistic infections – which ultimately cause death – and highly active antiretroviral therapy (HAART) designed to reduce viral load and replication. HAART is also the most e?ective way of preventing opportunistic infections, and has had a signi?cant impact in delaying the onset of AIDS in HIV-positive individuals in developed countries.
Four classes of drugs are currently in use. Nucleoside analogues, including ZIDOVUDINE and DIDANOSINE, interfere with the activity of the unique enzyme of the retrovirus reverse transcriptase which is essential for replication. Nucleotide analogues, such as tenofovir, act in the same way but require no intracellular activation. Non-nucleoside reverse transcriptase inhibitors, such as nevirapine and EFAVIRENZ, act by a di?erent mechanism on the same enzyme. The most potent single agents against HIV are the protease inhibitors, such as lopinavir, which render a unique viral enzyme ineffective. These drugs are used in a variety of combinations in an attempt to reduce the plasma HIV viral load to below detectable limits, which is achieved in approximately 90 per cent of patients who have not previously received therapy. This usually also produces a profound rise in CD4 count. It is likely, however, that such treatments need to be lifelong – and since they are associated with toxicities, long-term adherence is di?cult. Thus the optimum time for treatment intervention remains controversial, with some clinicians believing that this should be governed by the viral load rising above 10,000 copies, and others that it should primarily be designed to prevent the development of opportunistic infections – thus, that initiation of therapy should be guided more by the CD4 count.
It should be noted that the drug regimens have been devised for infection with HIV-1; it is not known how e?ective they are at treating infection with HIV-2.
HIV and pregnancy An HIV-positive woman can transmit the virus to her fetus, with the risk of infection being particularly high during parturition; however, the risk of perinatal HIV transmission can be reduced by antiviral drug therapy. In the UK, HIV testing is available to all women as part of antenatal care. The bene?ts of antenatal HIV testing in countries where antiviral drugs are not available are questionable. An HIV-positive woman might be advised not to breast feed because of the risks of transmitting HIV via breastmilk, but there may be a greater risk associated with not breast feeding at all. Babies in many poor communities are thought to be at high risk of infectious diseases and malnutrition if they are not breast fed and may thus be at greater overall risk of death during infancy.
Counselling Con?dential counselling is an essential part of AIDS management, both in terms of supporting the psychological wellbeing of the individual and in dealing with issues such as family relations, sexual partners and implications for employment (e.g. for health-care workers). Counsellors must be particularly sensitive to culture and lifestyle issues. Counselling is essential both before an HIV test is taken and when the results are revealed.
Health-care workers Health-care workers may be at risk of occupational exposure to HIV, either through undertaking invasive procedures or through accidental exposure to infected blood from a contaminated needle (needlestick injury). Needlestick injuries are frequent in health care – as many as 600,000 to 800,000 are thought to occur annually in the United States. Transmission is much more likely where the worker has been exposed to HIV through a needlestick injury or deep cut with a contaminated instrument than through exposure of mucous membranes to contaminated blood or body ?uids. However, even where exposure occurs through a needlestick injury, the risk of seroconversion is much lower than with a similar exposure to hepatitis C or hepatitis B. A percutaneous exposure to HIV-infected blood in a health-care setting is thought to carry a risk of about one infection per 300 injuries (one in 1,000 for mucous-membrane exposure), compared with one in 30 for hepatitis C, and one in three for hepatitis B (when the source patient is e-antigen positive).
In the event of an injury, health-care workers are advised to report the incident immediately where, depending on a risk assessment, they may be o?ered post-exposure prophylaxis (PEP). They should also wash the contaminated area with soap and water (but without scrubbing) and, if appropriate, encourage bleeding at the site of injury. PEP, using a combination of antiretroviral drugs (in a similar regimen to HAART – see above), is thought to greatly reduce the chances of seroconversion; it should be commenced as soon as possible, preferably within one or two hours of the injury. Although PEP is available, safe systems of work are considered to o?er the greatest protection. Double-gloving (latex gloves remove much of the blood from the surface of the needle during a needlestick), correct use of sharps containers (for used needles and instruments), avoiding the resheathing of used needles, reduction in the number of blood samples taken from a patient, safer-needle devices (such as needles that self-blunt after use) and needleless drug administration are all thought to reduce the risk of exposure to HIV and other blood-borne viruses. Although there have been numerous cases of health-care workers developing HIV through occupational exposure, there is little evidence of health-care workers passing HIV to their patients through normal medical procedures.... aids/hiv
A severe or life-threatening reaction is often termed ANAPHYLAXIS. Many immune mechanisms also contribute to allergic disorders; however, adverse reactions to drugs, diagnostic materials and other substances often do not involve recognised immunological mechanisms and the term ‘hypersensitivity’ is preferable. (See also IMMUNITY.)
Adverse reactions may manifest themselves as URTICARIA, wheezing or di?culty in breathing owing to spasm of the BRONCHIOLES, swollen joints, nausea, vomiting and headaches. Severe allergic reactions may cause a person to go into SHOCK. Although symptoms of an allergic reaction can usually be controlled, treatment of the underlying conditon is more problematic: hence, the best current approach is for susceptible individuals to ?nd out what it is they are allergic to and avoid those agents. For some people, such as those sensitive to insect venom, IMMUNOTHERAPY or desensitisation is often e?ective. If avoidance measures are unsuccessful and desensitisation ine?ective, the in?ammatory reactions can be controlled with CORTICOSTEROIDS, while the troublesome symptoms can be treated with ANTIHISTAMINE DRUGS and SYMPATHOMIMETICS. All three types of drugs may be needed to treat severe allergic reactions.
One interesting hypothesis is that reduced exposure to infective agents, such as bacteria, in infancy may provoke the development of allergy in later life.
Predicted developments in tackling allergic disorders, according to Professor Stephen Holgate writing in the British Medical Journal (22 January 2000) include:
Identi?cation of the principal environmental factors underlying the increase in incidence, to enable preventive measures to be planned.
Safe and e?ective immunotherapy to prevent and reverse allergic disease.
Treatments that target the protein reactions activated by antigens.
Identi?cation of how IgE is produced in the body, and thus of possible ways to inhibit this process.
Identi?cation of genes affecting people’s susceptibility to allergic disease.... allergy
Excessive appetite may simply be a bad habit, due to habitual over-indulgence in good food and resulting in GOUT, OBESITY, etc. – according to the other habits and constitution of the person. It may also be a sign of DIABETES MELLITUS or thyrotoxicosis (see under THYROID GLAND, DISEASES OF).
Diminished appetite is a sign common to almost all diseases causing general weakness, because the activity of the stomach and the secretion of gastric juice fail early when vital power is low. It is the most common sign of DYSPEPSIA due to gastritis, and of cancer of the stomach. In some cases it is a manifestation of stress or strain such as domestic worry or dif?culties at work. Indeed, appetite seems to be particularly susceptible to emotional disturbances, as is evidenced by the linked conditions of BULIMIA (pathological overeating) and anorexia nervosa (pathological dieting) – see also EATING DISORDERS.... appetite
Bone fractures These occur when there is a break in the continuity of the bone. This happens either as a result of violence or because the bone is unhealthy and unable to withstand normal stresses.
SIMPLE FRACTURES Fractures where the skin remains intact or merely grazed. COMPOUND FRACTURES have at least one wound which is in communication with the fracture, meaning that bacteria can enter the fracture site and cause infection. A compound fracture is also more serious than a simple fracture because there is greater potential for blood loss. Compound fractures usually need hospital admission, antibiotics and careful reduction of the fracture. Debridement (cleaning and excising dead tissue) in a sterile theatre may also be necessary.
The type of fracture depends on the force which has caused it. Direct violence occurs when an object hits the bone, often causing a transverse break – which means the break runs horizontally across the bone. Indirect violence occurs when a twisting injury to the ankle, for example, breaks the calf-bone (the tibia) higher up. The break may be more oblique. A fall on the outstretched hand may cause a break at the wrist, in the humerus or at the collar-bone depending on the force of impact and age of the person. FATIGUE FRACTURES These occur after the bone has been under recurrent stress. A typical example is the march fracture of the second toe, from which army recruits suffer after long marches. PATHOLOGICAL FRACTURES These occur in bone which is already diseased – for example, by osteoporosis (see below) in post-menopausal women. Such fractures are typically crush fractures of the vertebrae, fractures of the neck of the femur, and COLLES’ FRACTURE (of the wrist). Pathological fractures also occur in bone which has secondary-tumour deposits. GREENSTICK FRACTURES These occur in young children whose bones are soft and bend, rather than break, in response to stress. The bone tends to buckle on the side opposite to the force. Greenstick fractures heal quickly but still need any deformity corrected and plaster of Paris to maintain the correction. COMPLICATED FRACTURES These involve damage to important soft tissue such as nerves, blood vessels or internal organs. In these cases the soft-tissue damage needs as much attention as the fracture site. COMMINUTED FRACTURES A fracture with more than two fragments. It usually means that the injury was more violent and that there is more risk of damage to vessels and nerves. These fractures are unstable and take longer to unite. Rehabilitation tends to be protracted. DEPRESSED FRACTURES Most commonly found in skull fractures. A fragment of bone is forced inwards so that it lies lower than the level of the bone surrounding it. It may damage the brain beneath it.
HAIR-LINE FRACTURES These occur when the bone is broken but the force has not been severe enough to cause visible displacement. These fractures may be easily missed. Symptoms and signs The fracture site is usually painful, swollen and deformed. There is asymmetry of contour between limbs. The limb is held uselessly. If the fracture is in the upper
limb, the arm is usually supported by the patient; if it is in the lower limb then the patient is not able to bear weight on it. The limb may appear short because of muscle spasm.
Examination may reveal crepitus – a bony grating – at the fracture site. The diagnosis is con?rmed by radiography.
Treatment Healing of fractures (union) begins with the bruise around the fracture being resorbed and new bone-producing cells and blood vessels migrating into the area. Within a couple of days they form a bridge of primitive bone across the fracture. This is called callus.
The callus is replaced by woven bone which gradually matures as the new bone remodels itself. Treatment of fractures is designed to ensure that this process occurs with minimal residual deformity to the bone involved.
Treatment is initially to relieve pain and may involve temporary splinting of the fracture site. Reducing the fracture means restoring the bones to their normal position; this is particularly important at the site of joints where any small displacement may limit movement considerably.
with plaster of Paris. If closed traction does not work, then open reduction of the fracture may
be needed. This may involve ?xing the fracture with internal-?xation methods, using metal plates, wires or screws to hold the fracture site in a rigid position with the two ends closely opposed. This allows early mobilisation after fractures and speeds return to normal use.
External ?xators are usually metal devices applied to the outside of the limb to support the fracture site. They are useful in compound fractures where internal ?xators are at risk of becoming infected.
Consolidation of a fracture means that repair is complete. The time taken for this depends on the age of the patient, the bone and the type of fracture. A wrist fracture may take six weeks, a femoral fracture three to six months in an adult.
Complications of fractures are fairly common. In non-union, the fracture does not unite
– usually because there has been too much mobility around the fracture site. Treatment may involve internal ?xation (see above). Malunion means that the bone has healed with a persistent deformity and the adjacent joint may then develop early osteoarthritis.
Myositis ossi?cans may occur at the elbow after a fracture. A big mass of calci?ed material develops around the fracture site which restricts elbow movements. Late surgical removal (after 6–12 months) is recommended.
Fractured neck of FEMUR typically affects elderly women after a trivial injury. The bone is usually osteoporotic. The leg appears short and is rotated outwards. Usually the patient is unable to put any weight on the affected leg and is in extreme pain. The fractures are classi?ed according to where they occur:
subcapital where the neck joins the head of the femur.
intertrochanteric through the trochanter.
subtrochanteric transversely through the upper end of the femur (rare). Most of these fractures of the neck of femur
need ?xing by metal plates or hip replacements, as immobility in this age group has a mortality of nearly 100 per cent. Fractures of the femur shaft are usually the result of severe trauma such as a road accident. Treatment may be conservative or operative.
In fractures of the SPINAL COLUMN, mere damage to the bone – as in the case of the so-called compression fracture, in which there is no damage to the spinal cord – is not necessarily serious. If, however, the spinal cord is damaged, as in the so-called fracture dislocation, the accident may be a very serious one, the usual result being paralysis of the parts of the body below the level of the injury. Therefore the higher up the spine is fractured, the more serious the consequences. The injured person should not be moved until skilled assistance is at hand; or, if he or she must be removed, this should be done on a rigid shutter or door, not on a canvas stretcher or rug, and there should be no lifting which necessitates bending of the back. In such an injury an operation designed to remove a displaced piece of bone and free the spinal cord from pressure is often necessary and successful in relieving the paralysis. DISLOCATIONS or SUBLUXATION of the spine are not uncommon in certain sports, particularly rugby. Anyone who has had such an injury in the cervical spine (i.e. in the neck) should be strongly advised not to return to any form of body-contact or vehicular sport.
Simple ?ssured fractures and depressed fractures of the skull often follow blows or falls on the head, and may not be serious, though there is always a risk of damage which is potentially serious to the brain at the same time.
Compound fractures may result in infection within the skull, and if the skull is extensively broken and depressed, surgery is usually required to check any intercranial bleeding or to relieve pressure on the brain.
The lower jaw is often fractured by a blow on the face. There is generally bleeding from the mouth, the gum being torn. Also there are pain and grating sensations on chewing, and unevenness in the line of the teeth. The treatment is simple, the line of teeth in the upper jaw forming a splint against which the lower jaw is bound, with the mouth closed.
Congenital diseases These are rare but may produce certain types of dwar?sm or a susceptibility to fractures (osteogenesis imperfecta).
Infection of bone (osteomyelitis) may occur after an open fracture, or in newborn babies with SEPTICAEMIA. Once established it is very di?cult to eradicate. The bacteria appear capable of lying dormant in the bone and are not easily destroyed with antibiotics so that prolonged treatment is required, as might be surgical drainage, exploration or removal of dead bone. The infection may become chronic or recur.
Osteomalacia (rickets) is the loss of mineralisation of the bone rather than simple loss of bone mass. It is caused by vitamin D de?ciency and is probably the most important bone disease in the developing world. In sunlight the skin can synthesise vitamin D (see APPENDIX 5: VITAMINS), but normally rickets is caused by a poor diet, or by a failure to absorb food normally (malabsorbtion). In rare cases vitamin D cannot be converted to its active state due to the congenital lack of the speci?c enzymes and the rickets will fail to respond to treatment with vitamin D. Malfunction of the parathyroid gland or of the kidneys can disturb the dynamic equilibrium of calcium and phosphate in the body and severely deplete the bone of its stores of both calcium and phosphate.
Osteoporosis A metabolic bone disease resulting from low bone mass (osteopenia) due to excessive bone resorption. Su?erers are prone to bone fractures from relatively minor trauma. With bone densitometry it is now possible to determine individuals’ risk of osteoporosis and monitor their response to treatment.
By the age of 90 one in two women and one in six men are likely to sustain an osteoporosis-related fracture. The incidence of fractures is increasing more than would be expected from the ageing of the population, which may re?ect changing patterns of exercise or diet.
Osteoporosis may be classi?ed as primary or secondary. Primary consists of type 1 osteoporosis, due to accelerated trabecular bone loss, probably as a result of OESTROGENS de?ciency. This typically leads to crush fractures of vertebral bodies and fractures of the distal forearm in women in their 60s and 70s. Type 2 osteoporosis, by contrast, results from the slower age-related cortical and travecular bone loss that occurs in both sexes. It typically leads to fractures of the proximal femur in elderly people.
Secondary osteoporosis accounts for about 20 per cent of cases in women and 40 per cent of cases in men. Subgroups include endocrine (thyrotoxicosis – see under THYROID GLAND, DISEASES OF, primary HYPERPARATHYROIDISM, CUSHING’S SYNDROME and HYPOGONADISM); gastrointestinal (malabsorption syndrome, e.g. COELIAC DISEASE, or liver disease, e.g. primary biliary CIRRHOSIS); rheumatological (RHEUMATOID ARTHRITIS or ANKYLOSING SPONDYLITIS); malignancy (multiple MYELOMA or metastatic CARCINOMA); and drugs (CORTICOSTEROIDS, HEPARIN). Additional risk factors for osteoporosis include smoking, high alcohol intake, physical inactivity, thin body-type and heredity.
Individuals at risk of osteopenia, or with an osteoporosis-related fracture, need investigation with spinal radiography and bone densitometry. A small fall in bone density results in a large increase in the risk of fracture, which has important implications for preventing and treating osteoporosis.
Treatment Antiresorptive drugs: hormone replacement therapy – also valuable in treating menopausal symptoms; treatment for at least ?ve years is necessary, and prolonged use may increase risk of breast cancer. Cyclical oral administration of disodium etidronate – one of the bisphosphonate group of drugs – with calcium carbonate is also used (poor absorption means the etidronate must be taken on an empty stomach). Calcitonin – currently available as a subcutaneous injection; a nasal preparation with better tolerance is being developed. Calcium (1,000 mg daily) seems useful in older patients, although probably ine?ective in perimenopausal women, and it is a safe preparation. Vitamin D and calcium – recent evidence suggests value for elderly patients. Anabolic steroids, though androgenic side-effects (masculinisation) make these unacceptable for most women.
With established osteoporosis, the aim of treatment is to relieve pain (with analgesics and physical measures, e.g. lumbar support) and reduce the risk of further fractures: improvement of bone mass, the prevention of falls, and general physiotherapy, encouraging a healthier lifestyle with more daily exercise.
Further information is available from the National Osteoporosis Society.
Paget’s disease (see also separate entry) is a common disease of bone in the elderly, caused by overactivity of the osteoclasts (cells concerned with removal of old bone, before new bone is laid down by osteoblasts). The bone affected thickens and bows and may become painful. Treatment with calcitonin and bisphosphonates may slow down the osteoclasts, and so hinder the course of the disease, but there is no cure.
If bone loses its blood supply (avascular necrosis) it eventually fractures or collapses. If the blood supply does not return, bone’s normal capacity for healing is severely impaired.
For the following diseases see separate articles: RICKETS; ACROMEGALY; OSTEOMALACIA; OSTEOGENESIS IMPERFECTA.
Tumours of bone These can be benign (non-cancerous) or malignant (cancerous). Primary bone tumours are rare, but secondaries from carcinoma of the breast, prostate and kidneys are relatively common. They may form cavities in a bone, weakening it until it breaks under normal load (a pathological fracture). The bone eroded away by the tumour may also cause problems by causing high levels of calcium in the plasma.
EWING’S TUMOUR is a malignant growth affecting long bones, particularly the tibia (calfbone). The presenting symptoms are a throbbing pain in the limb and a high temperature. Treatment is combined surgery, radiotherapy and chemotherapy.
MYELOMA is a generalised malignant disease of blood cells which produces tumours in bones which have red bone marrow, such as the skull and trunk bones. These tumours can cause pathological fractures.
OSTEOID OSTEOMA is a harmless small growth which can occur in any bone. Its pain is typically removed by aspirin.
OSTEOSARCOMA is a malignant tumour of bone with a peak incidence between the ages of ten and 20. It typically involves the knees, causing a warm tender swelling. Removal of the growth with bone conservation techniques can often replace amputation as the de?nitive treatment. Chemotherapy can improve long-term survival.... bone, disorders of
Nutritional Profile Energy value (calories per serving): Moderate Protein: High Fat: High Saturated fat: Moderate Cholesterol: High Carbohydrates: Low Fiber: None Sodium: Moderate to high Major vitamin contribution: Vitamin A, riboflavin, vitamin D Major mineral contribution: Iron, calcium
About the Nutrients in This Food An egg is really three separate foods, the whole egg, the white, and the yolk, each with its own distinct nutritional profile. A whole egg is a high-fat, high-cholesterol, high-quality protein food packaged in a high-calcium shell that can be ground and added to any recipe. The proteins in eggs, with sufficient amounts of all the essential amino acids, are 99 percent digestible, the standard by which all other proteins are judged. The egg white is a high-protein, low-fat food with virtually no cholesterol. Its only important vitamin is riboflavin (vitamin B2), a vis- ible vitamin that gives egg white a slightly greenish cast. Raw egg whites contain avidin, an antinutrient that binds biotin a B complex vitamin for- merly known as vitamin H, into an insoluble compound. Cooking the egg inactivates avidin. An egg yolk is a high-fat, high-cholesterol, high-protein food, a good source of vitamin A derived from carotenes eaten by the laying hen, plus vitamin D, B vitamins, and heme iron, the form of iron most easily absorbed by your body. One large whole egg (50 g/1.8 ounce) has five grams fat (1.5 g satu- rated fat, 1.9 g monounsaturated fat, 0.7 g polyunsaturated fat), 212 mg cholesterol, 244 IU vitamin A (11 percent of the R DA for a woman, 9 percent * Values are for a whole egg. of the R DA for a man), 0.9 mg iron (5 percent of the R DA for a woman, 11 percent of the R DA for a man) and seven grams protein. The fat in the egg is all in the yolk. The protein is divided: four grams in the white, three grams in the yolk.
The Most Nutritious Way to Serve This Food With extra whites and fewer yolks to lower the fat and cholesterol per serving.
Diets That May Restrict or Exclude This Food Controlled-fat, low-cholesterol diet Low-protein diet
Buying This Food Look for: Eggs stored in the refrigerated dair y case. Check the date for freshness. NOTE : In 1998, the FDA and USDA Food Safety and Inspection Service (FSIS) proposed new rules that would require distributors to keep eggs refrigerated on the way to the store and require stores to keep eggs in a refrigerated case. The egg package must have a “refrigera- tion required” label plus safe-handling instructions on eggs that have not been treated to kill Salmonella. Look for: Eggs that fit your needs. Eggs are graded by the size of the yolk and the thick- ness of the white, qualities that affect appearance but not nutritional values. The higher the grade, the thicker the yolk and the thicker the white will be when you cook the egg. A Grade A A egg fried sunny side up will look much more attractive than a Grade B egg prepared the same way, but both will be equally nutritions. Egg sizes ( Jumbo, Extra large, Large, Medium, Small) are determined by how much the eggs weigh per dozen. The color of the egg’s shell depends on the breed of the hen that laid the egg and has nothing to do with the egg’s food value.
Storing This Food Store fresh eggs with the small end down so that the yolk is completely submerged in the egg white (which contains antibacterial properties, nature’s protection for the yolk—or a developing chick embryo in a fertilized egg). Never wash eggs before storing them: The water will make the egg shell more porous, allowing harmful microorganisms to enter. Store separated leftover yolks and whites in small, tightly covered containers in the refrigerator, where they may stay fresh for up to a week. Raw eggs are very susceptible to Salmonella and other bacterial contamination; discard any egg that looks or smells the least bit unusual. Refrigerate hard-cooked eggs, including decorated Easter eggs. They, too, are suscep- tible to Salmonella contamination and should never be left at room temperature.
Preparing This Food First, find out how fresh the eggs really are. The freshest ones are the eggs that sink and lie flat on their sides when submerged in cool water. These eggs can be used for any dish. By the time the egg is a week old, the air pocket inside, near the broad end, has expanded so that the broad end tilts up as the egg is submerged in cool water. The yolk and the white inside have begun to separate; these eggs are easier to peel when hard-cooked. A week or two later, the egg’s air pocket has expanded enough to cause the broad end of the egg to point straight up when you put the egg in water. By now the egg is runny and should be used in sauces where it doesn’t matter if it isn’t picture-perfect. After four weeks, the egg will float. Throw it away. Eggs are easily contaminated with Salmonella microorganisms that can slip through an intact shell. never eat or serve a dish or bever age containing r aw fr esh eggs. sa lmonella is destroyed by cooking eggs to an inter nal temper atur e of 145°f ; egg-milk dishes such as custar ds must be cooked to an inter nal temper atur e of 160°f. If you separate fresh eggs by hand, wash your hands thoroughly before touching other food, dishes, or cooking tools. When you have finished preparing raw eggs, wash your hands and all utensils thoroughly with soap and hot water. never stir cooked eggs with a utensil used on r aw eggs. When you whip an egg white, you change the structure of its protein molecules which unfold, breaking bonds between atoms on the same molecule and forming new bonds to atoms on adjacent molecules. The result is a network of protein molecules that hardens around air trapped in bubbles in the net. If you beat the whites too long, the foam will turn stiff enough to hold its shape even if you don’t cook it, but it will be too stiff to expand natu- rally if you heat it, as in a soufflé. When you do cook properly whipped egg white foam, the hot air inside the bubbles will expand. Ovalbumin, an elastic protein in the white, allows the bubble walls to bulge outward until they are cooked firm and the network is stabilized as a puff y soufflé. The bowl in which you whip the whites should be absolutely free of fat or grease, since the fat molecules will surround the protein molecules in the egg white and keep them from linking up together to form a puff y white foam. Eggs whites will react with metal ions from the surface of an aluminum bowl to form dark particles that discolor the egg-white foam. You can whip eggs successfully in an enamel or glass bowl, but they will do best in a copper bowl because copper ions bind to the egg and stabilize the foam.
What Happens When You Cook This Food When you heat a whole egg, its protein molecules behave exactly as they do when you whip an egg white. They unfold, form new bonds, and create a protein network, this time with molecules of water caught in the net. As the egg cooks, the protein network tightens, squeez- ing out moisture, and the egg becomes opaque. The longer you cook the egg, the tighter the network will be. If you cook the egg too long, the protein network will contract strongly enough to force out all the moisture. That is why overcooked egg custards run and why overcooked eggs are rubbery. If you mix eggs with milk or water before you cook them, the molecules of liquid will surround and separate the egg’s protein molecules so that it takes more energy (higher heat) to make the protein molecules coagulate. Scrambled eggs made with milk are softer than plain scrambled eggs cooked at the same temperature. When you boil an egg in its shell, the air inside expands and begins to escape through the shell as tiny bubbles. Sometimes, however, the force of the air is enough to crack the shell. Since there’s no way for you to tell in advance whether any particular egg is strong enough to resist the pressure of the bubbling air, the best solution is to create a safety vent by sticking a pin through the broad end of the egg before you start to boil it. Or you can slow the rate at which the air inside the shell expands by starting the egg in cold water and letting it warm up naturally as the water warms rather than plunging it cold into boiling water—which makes the air expand so quickly that the shell is virtually certain to crack. As the egg heats, a little bit of the protein in its white will decompose, releasing sulfur that links up with hydrogen in the egg, forming hydrogen sulfide, the gas that gives rot- ten eggs their distinctive smell. The hydrogen sulfide collects near the coolest part of the egg—the yolk. The yolk contains iron, which now displaces the hydrogen in the hydrogen sulfide to form a green iron-sulfide ring around the hard-cooked yolk.
How Other Kinds of Processing Affect This Food Egg substitutes. Fat-free, cholesterol-free egg substitutes are made of pasteurized egg whites, plus artificial or natural colors, flavors, and texturizers (food gums) to make the product look and taste like eggs, plus vitamins and minerals to produce the nutritional equivalent of a full egg. Pasteurized egg substitutes may be used without additional cooking, that is, in salad dressings and eggnog. Drying. Dried eggs have virtually the same nutritive value as fresh eggs. Always refrigerate dried eggs in an air- and moistureproof container. At room temperature, they will lose about a third of their vitamin A in six months.
Medical Uses and/or Benefits Protein source. The protein in eggs, like protein from all animal foods, is complete. That is, protein from animal foods provides all the essential amino acids required by human beings. In fact, the protein from eggs is so well absorbed and utilized by the human body that it is considered the standard by which all other dietary protein is measured. On a scale known as biological value, eggs rank 100 ; milk, 93; beef and fish, 75; and poultry, 72. Vision protection. The egg yolk is a rich source of the yellow-orange carotenoid pigments lutein and zeaxanthin. Both appear to play a role in protecting the eyes from damaging ultraviolet light, thus reducing the risk of cataracts and age-related macular degeneration, a leading cause of vision of loss in one-third of all Americans older than 75. Just 1.3 egg yolks a day appear to increase blood levels of lutein and zeaxanthin by up to 128 percent. Perhaps as a result, data released by the National Eye Institute’s 6,000-person Beaver Dam ( Wisconsin) Eye Study in 2003 indicated that egg consumption was inversely associated with cataract risk in study participants who were younger than 65 years of age when the study started. The relative risk of cataracts was 0.4 for people in the highest category of egg consumption, compared to a risk of 1.0 for those in the lowest category. External cosmetic effects. Beaten egg whites can be used as a facial mask to make your skin look smoother temporarily. The mask works because the egg proteins constrict as they dry on your face, pulling at the dried layer of cells on top of your skin. When you wash off the egg white, you also wash off some of these loose cells. Used in a rinse or shampoo, the pro- tein in a beaten raw egg can make your hair look smoother and shinier temporarily by filling in chinks and notches on the hair shaft.
Adverse Effects Associated with This Food Increased risk of cardiovascular disease. Although egg yolks are high in cholesterol, data from several recent studies suggest that eating eggs may not increase the risk of heart disease. In 2003, a report from a 14-year, 177,000-plus person study at the Harvard School of Public Health showed that people who eat one egg a day have exactly the same risk of heart disease as those who eat one egg or fewer per week. A similar report from the Multiple R isk Factor Intervention Trial showed an inverse relationship between egg consumption and cholesterol levels—that is, people who ate more eggs had lower cholesterol levels. Nonetheless, in 2006 the National Heart, Lung, and Blood Institute still recommends no more than four egg yolks a week (including the yolk in baked goods) for a heart-healthy diet. The American Heart Association says consumers can have one whole egg a day if they limit cholesterol from other sources to the amount suggested by the National Cholesterol Education Project following the Step I and Step II diets. (Both groups permit an unlimited number of egg whites.) The Step I diet provides no more than 30 percent of total daily calories from fat, no more than 10 percent of total daily calories from saturated fat, and no more than 300 mg of cholesterol per day. It is designed for healthy people whose cholesterol is in the range of 200 –239 mg/dL. The Step II diet provides 25– 35 percent of total calories from fat, less than 7 percent of total calories from saturated fat, up to 10 percent of total calories from polyunsaturated fat, up to 20 percent of total calories from monounsaturated fat, and less than 300 mg cho- lesterol per day. This stricter regimen is designed for people who have one or more of the following conditions: • Existing cardiovascular disease • High levels of low-density lipoproteins (LDLs, or “bad” cholesterol) or low levels of high-density lipoproteins (HDLs, or “good” cholesterol) • Obesity • Type 1 diabetes (insulin-dependent diabetes, or diabetes mellitus) • Metabolic syndrome, a.k.a. insulin resistance syndrome, a cluster of risk fac- tors that includes type 2 diabetes (non-insulin-dependent diabetes) Food poisoning. Raw eggs (see above) and egg-rich foods such as custards and cream pies are excellent media for microorganisms, including the ones that cause food poisoning. To protect yourself against egg-related poisoning, always cook eggs thoroughly: poach them five minutes over boiling water or boil at least seven minutes or fry two to three minutes on each side (no runny center) or scramble until firm. Bread with egg coating, such as French toast, should be cooked crisp. Custards should be firm and, once cooked, served very hot or refrigerated and served very cold. Allergic reaction. According to the Merck Manual, eggs are one of the 12 foods most likely to trigger the classic food allergy symptoms: hives, swelling of the lips and eyes, and upset stomach. The others are berries (blackberries, blueberries, raspberries, strawberries), choco- late, corn, fish, legumes (green peas, lima beans, peanuts, soybeans), milk, nuts, peaches, pork, shellfish, and wheat (see wheat cer ea ls).
Food/Drug Interactions Sensitivity to vaccines. Live-virus measles vaccine, live-virus mumps vaccine, and the vac- cines for influenza are grown in either chick embryo or egg culture. They may all contain minute residual amounts of egg proteins that may provoke a hypersensitivity reaction in people with a history of anaphylactic reactions to eggs (hives, swelling of the mouth and throat, difficulty breathing, a drop in blood pressure, or shock).... eggs
The most widely prescribed type of antidepressants are the tricyclics, so-called because their molecular structure includes three rings. The other commonly used types are named after the actions they have on chemicals in the brain: the SELECTIVE SEROTONIN-REUPTAKE INHIBITORS (SSRIS) and the MONOAMINE OXIDASE INHIBITORS (MAOIS) – see also below. All types of antidepressant work in similar ways. Tricyclic antidepressants have cured depression in millions of people, but they can cause unpleasant side-effects, particularly in the ?rst couple of weeks. These include SEDATION, dry mouth, excessive sweating, CONSTIPATION, urinary problems, and impotence (inability to get an erection). Up to half of all people prescribed tricyclic drugs cannot tolerate the side-effects and stop treatment before their depression is properly treated. More seriously, tricyclics can upset the rhythm of the heart in susceptible people and should never be given in the presence of heart disease.
The SSRIs are newer, coming into wide use in the late 1980s. They increase the levels in the brain of the chemical messenger SEROTONIN, which is thought to be depleted in depression. Indeed, the SSRIs are as e?ective as tricyclics and, although they can cause nausea and excessive sweating at ?rst, they generally have fewer side-effects. Their main disadvantage, however, is that they cost much more than the most commonly used tricyclic, amitriptyline. On the other hand, they are more acceptable to many patients and they cause fewer drop-outs from treatment – up to a quarter rather than a half. The money saved by completed, successful treatment may outweigh the prescribing costs. SSRIs have been reported as associated with an increased risk of suicide.
Another group of antidepressants, the MAOIs, have been in use since the late 1950s.
They are stimulants, rather than sedatives, and are particularly helpful for people who are physically and mentally slowed by depression. They work well but have one big disadvantage – a dangerous interaction with certain foods and other drugs, causing a sudden and very dangerous increase in blood pressure. People taking them must carry an information card explaining the risk and listing the things that they should avoid. Because of this risk, MAOIs are not used much now, except when other treatments have failed. A new MAOI, moclobemide, which is less likely to interact and so cause high blood pressure, is now available.
LITHIUM CARBONATE is a powerful antidepressant used for intractable depression. It should be used under specialist supervision as the gap between an e?ective dose and a toxic one is narrow.
St John’s Wort is a popular herbal remedy which may be e?ective, but which is handicapped by di?erences of strength between di?erent preparations or batches. It can interact with a number of conventional drugs and so needs to be used cautiously and with advice.
In general, antidepressants work by restoring the balance of chemicals in the brain. Improved sleep and reduced anxiety are usually the ?rst signs of improvement, particularly among people taking the more sedative tricyclic drugs. Improvement in other symptoms follow, with the mood starting to lift after about two weeks of treatment. Most people feel well by three months, although a few residual symptoms, such as slowness in the mornings, may take longer to clear up. People taking antidepressants usually want to stop them as soon as they feel better; however, the risk of relapse is high for up to a year and most doctors recommend continuing the drugs for around 4–6 months after recovery, with gradual reduction of the dose after that.
Withdrawal reactions may occur including nausea, vomiting, headache, giddiness, panic or anxiety and restlessness. The drugs should be withdrawn gradually over about a month or longer (up to six months in those who have been on maintenance treatment).
A wide range of antidepressant drugs is described in the British National Formulary. Examples include:
Tricyclics: amitryptyline, imipramine, doxepin.
MAOIs: phenelzine, isocarboxazid.
SSRIs: citalopram, ?uoxetine, paraxtene. (Antidepressant drugs not in these three
groups include ?upenthixol, mertazapine and venlafaxine.)... antidepressant drugs
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
A pre-vaccination tuberculin test is necessary in all age-groups except newborn infants, and only those with negative tuberculin reactions are vaccinated. Complications are few and far between. A local reaction at the site of vaccination usually occurs between two and six weeks after vaccination, beginning as a small papule that slowly increases in size. It may produce a small ulcer. This heals after around two months, leaving a small scar. (See IMMUNITY; TUBERCULIN.)... bcg vaccine
Recently chemotherapy has become increasingly e?ective in the treatment of cancer. Numerous drugs, generally CYTOTOXIC, are available; great care is required in their selection and to minimise side-effects. Certain tumours are highly sensitive to chemotherapy
– especially testicular tumours, LEUKAEMIA, LYMPHOMA and various tumours occurring in childhood (e.g. Wilm’s tumour – see NEPHROBLASTOMA) – and may even be cured.... chemotherapy
It usually begins in infancy but may flare up during adolescence and adulthood.
The cause is unknown, but people with atopy are more susceptible.... atopic eczema
The potential side-effects of diuretics are HYPOKALAEMIA, DEHYDRATION, and GOUT (in susceptible individuals).
Extra-renal mechanisms (a) Inhibiting release of antidiuretic hormone (e.g. water, alcohol); (b) increased renal blood ?ow (e.g. dopamine in renal doses).
Renal mechanisms (a) Osmotic diuretics act by ‘holding’ water in the renal tubules and preventing its reabsorption (e.g. mannitol); (b) loop diuretics prevent sodium, and therefore water, reabsorption (e.g. FRUSEMIDE); (c) drugs acting on the cortical segment of the Loop of Henle prevent sodium reabsorption, but are ‘weaker’ than loop diuretics (e.g. THIAZIDES); (d) drugs acting on the distal tubule prevent sodium reabsorption by retaining potassium
(e.g. spironalactone).... diuretics
Fats are divided into saturated fats – that is, animal fats and dairy produce; and unsaturated fats, which include vegetable oils from soya bean, maize and sun?ower, and marine oils from ?sh (e.g. cod-liver oil). (See also ADIPOSE TISSUE; LIPID; OBESITY.)
Body fat Most of the body’s fat is stored in ADIPOSE TISSUE which is mainly sited beneath the skin and around various internal organs. Some, however, is stored in liver, muscle and other cellular structures such as bone marrow (see BONE). Various methods can be used to estimate the body’s fat content but all are indirect and not very accurate, depending as they do on hard-to-measure di?erences in composition between fat and lean tissues. The average body fat of healthy young men and women is below 20 per cent and 25 per cent respectively of their body weight. In economically developed countries, middle-aged men and women usually undergo a steady increase in body fat. This is probably not a feature of ageing, however, since in developing nations, which have di?erent diets and greater levels of physical activity, increased age does not bring with it an increase in body fat. One widely used means to estimate whether a person has excess fat is to measure his or her skinfold thickness on the arms and torso. The distribution of fat can be a pointer to certain disorders: those adults, for example, who deposit their fat abdominally rather than on their hips – an android rather than a gynaecoid distribution – are particularly susceptible to disease of the CARDIOVASCULAR SYSTEM and to DIABETES MELLITUS.
Adipose tissue comprises fat deposited as a result of eating more food than is metabolised by exercise and the body’s basic energy needs. Surplus fat can in some circumstances be a useful energy store. For example, hibernating animals ‘burn o?’ the fat stored during the summer months and are much leaner when they wake up in the spring. Excessive quantities of adipose tissue result in OBESITY, an increasingly serious problem among all age groups, including children, in countries with developed economies.... fat
Humidity is expressed as relative humidity (RH). This is the amount of moisture in the air expressed as a percentage of the maximum possible at that temperature. If the temperature of a room is raised without increasing the moisture content, the RH falls. The average outdoor RH in Britain is around 70–80 per cent; with central heating it may drop to 25 per cent or lower. This is why humidi?cation, as it is known, of the air is essential in buildings heated by modern heating systems. The aim should be to keep the RH at around 30–50 per cent. In houses this may be achieved quite satisfactorily by having a jug or basin of water in the room, or some receptacle that can be attached to the heater. In o?ces, some more elaborate form of humidi?er is necessary. Those suffering from chronic BRONCHITIS are particularly susceptible to dry air, as are those individuals with disorders of the EYE because the secretions that bathe the eyes and keep them moist are unnaturally dried out. (See also VENTILATION.)... humidification
Symptoms vary according to personality, environment, and the severity of illness.
They may include failure to understand events or remember what has been happening, physical restlessness, mood swings, hallucinations, and terrified panic.
High fever and disturbances of body chemistry are commonly present.
Children and older people are most susceptible to delirium, particularly during infection, after surgery, or when there is a pre-existing brain disturbance such as dementia.
Drugs, poisons, and alcohol are common precipitants.... delirium
Fibrous covering disclosing agents Dyes that make the plaque deposits on teeth more visible so that they can be seen and removed. discoid lupus erythematosus A form of the chronic autoimmune disorder lupus erythematosus.... disc, intervertebral
Normally, a young child requires a smaller dose than an adult. There are, however, other factors than age to be taken into consideration. Thus, children are more susceptible than adults to some drugs such as MORPHINE, whilst they are less sensitive to others such as ATROPINE. The only correct way to calculate a child’s dose is by reference to texts supplying a recommended dose in milligrams per kilogram. However, many reference texts simply quote doses for certain age-ranges.
Old people, too, often show an increased susceptibility to drugs. This is probably due to a variety of factors, such as decreased weight; diminished activity of the tissues and therefore diminished rate at which a drug is utilised; and diminished activity of the KIDNEYS resulting in decreased rate of excretion of the drug.
Weight and sex have both to be taken into consideration. Women require slightly smaller doses than men, probably because they tend to be lighter in weight. The e?ect of weight on dosage is partly dependent on the fact that much of the extra weight of a heavy individual is made up of fatty tissue which is not as active as other tissues of the body. In practice, the question of weight seldom makes much di?erence unless the individual is grossly over- or underweight.
Idiosyncrasy occasionally causes drugs administered in the ordinary dose to produce unexpected effects. Thus, some people are but little affected by some drugs, whilst in others, certain drugs – for example, psychoactive preparations such as sedatives – produce excessive symptoms in normal or even small doses. In some cases this may be due to hypersensitivity, or an allergic reaction, to the drug, which is a possibility that must always be borne in mind
(e.g. with PENICILLIN). An individual who is known to be allergic to a certain medication is strongly advised to carry a card to this e?ect, and always to inform medical and dental practitioners and/or a pharmacist before accepting a new prescription or buying an over-the-counter preparation.
Habitual use of a drug is perhaps the in?uence that causes the greatest increase in the dose necessary to produce the requisite e?ect. The classical example of this is with OPIUM and its derivatives.
Disease may modify the dose of medicines. This can occur in several ways. Thus, in serious illnesses the patient may be more susceptible to drugs, such as narcotics, that depress tissue activity, and therefore smaller doses must be given. Again, absorption of the drug from the gut may be slowed up by disease of the gut, or its e?ect may be enhanced if there is disease of the kidneys, interfering with the excretion of the drug.
Fasting aids the rapidity of absorption of drugs, and also makes the body more susceptible to their action. Partly for this reason, as well as to avoid irritation of the stomach, it is usual to prescribe drugs to be taken after meals, and diluted with water.
Combination of drugs is to be avoided if possible as it is often di?cult to assess what their combined e?ect may be. In some cases they may have a mutually antagonistic e?ect, which means that the patient will not obtain full bene?t. Sometimes a combination may have a deleterious e?ect.
Form, route and frequency of administration Drugs are now produced in many forms, though tablets are the most common and, usually, convenient. In Britain, medicines are given by mouth whenever possible, unless there is some degree of urgency, or because the drug is either destroyed in, or is not absorbed from, the gut. In these circumstances, it is given intravenously, intra-muscularly or subcutaneously. In some cases, as in cases of ASTHMA or BRONCHITIS, the drug may be given in the form of an inhalant (see INHALANTS), in order to get the maximum concentration at the point where it is wanted: that is, in the lungs. If a local e?ect is wanted, as in cases of diseases of the skin, the drug is applied topically to the skin. In some countries there is a tendency to give medicines in the form of a suppository which is inserted in the rectum.
Recent years have seen developments whereby the assimilation of drugs into the body can be more carefully controlled. These include, for example, what are known as transdermals, in which drugs are built into a plaster that is stuck on the skin, and the drug is then absorbed into the body at a controlled rate. This method is now being used for the administration of GLYCERYL TRINITRATE in the treatment of ANGINA PECTORIS, and of hyoscine hydrobromide in the treatment of MOTION (TRAVEL) SICKNESS. Another is a new class of implantable devices. These are tiny polymers infused with a drug and implanted just under the skin by injection. They can be tailored so as to deliver drugs at virtually any rate – from minutes to years. A modi?cation of these polymers now being investigated is the incorporation of magnetic particles which allow an extra burst of the incorporated drug to be released in response to an oscillating magnetic ?eld which is induced by a magnetic ‘watch’ worn by the patient. In this way the patient can switch on an extra dose of drug when this is needed: insulin, for instance, in the case of diabetics. In yet another new development, a core of drug is enclosed in a semi-permeable membrane and is released in the stomach at a given rate. (See also LIPOSOMES.)... dosage
The hands are highly susceptible to injury. Dermatitis is also common. The hand may be affected by Dupuytren’s contracture or Volkmann’s contracture. Degeneration of a tendon sheath on the upper side of the wrist may cause a harmless swelling called a ganglion. Osteoarthritis commonly affects the joint at the base of the thumb. Rheumatoid arthritis may cause deformity.... hand
Photosensitivity usually causes a rash on skin exposed to sunlight.
This often occurs because a photosensitizer (such as some drugs, dyes, chemicals in perfumes and soaps, and plants such as mustard) has been ingested or applied to the skin.
Photosensitivity is also a feature of disorders such as systemic lupus erythematosus.
People who are susceptible to photosensitivity reactions should avoid exposure to sunlight and photosensitizers, and use sunscreens.... photosensitivity
Severe hypothermia is sometimes complicated by gastric erosions and haemorrhage, as well as pancreatitis (see PANCREAS, DISORDERS OF). Infants and the elderly are less e?cient at regulating temperature and conserving heat than other age groups, and are therefore more at risk from accidental hypothermia during cold weather if their accommodation is not warm enough. Approximately half a million elderly people are at risk in Britain each winter from hypothermia. The other major cause of accidental hypothermia is near-drowning in icy water. Deliberate hypothermia is sometimes used to reduce metabolic rate so that prolonged periods of cardiac arrest may occur without tissue HYPOXIA developing. This technique is used for some cardiac and neurosurgical operations and is produced by immersion of the anaesthetised patient in iced water or by cooling an extracorporeal circulation.
Treatment of hypothermia is by warming the patient and treating any complications that arise. Passive warming is usual, with conservation of the patient’s own body heat with insulating blankets. If the core temperature is below 28 °C, then active rewarming should be instituted by means of warm peritoneal, gastric or bladder lavage or using an extracorporeal circulation. Care must be taken in moving hypothermic patients, as a sudden rush of cold peripheral blood to the heart can precipitate ventricular ?brillation. Prevention of hypothermia in the elderly is important. Special attention must be paid to diet, heating the home and adequate clothing in several layers to limit heat loss.... hypothermia
Age Disease and mode of administration
3 days BCG (Bacille Calmette-Guerin) by injection if tuberculosis in family in past 6 months.
2 months Poliomyelitis (oral); adsorbed diphtheria, whooping-cough (pertussis)1 and tetanus2 (triple vaccine given by injection); HiB injection.3
3 months Poliomyelitis (oral); diphtheria, whooping-cough (pertussis)1 and tetanus2 (triple vaccine given by injection); HiB injection.3
4 months Poliomyelitis (oral); diphtheria, whooping-cough (pertussis)1 and tetanus2 (triple vaccine given by injection); HiB injection.3
12–18 months Measles, mumps, and rubella (German measles)4 (given together live by injection).
(SCHOOL ENTRY)
4–5 years Poliomyelitis (oral); adsorbed diphtheria and tetanus (given together by injection); give MMR vaccine if not already given at 12–18 months.
10–14 females Rubella (by injection) if they have missed MMR.
10–14 BCG (Bacille Calmette-Guerin) by injection to tuberculin-negative children to prevent tuberculosis.
15–18 Poliomyelitis single booster dose (oral); tetanus (by injection).
1 Pertussis may be excluded in certain susceptible individuals.
2 Known as DPT or triple vaccine.
3 Haemophilus in?uenzae immunisation (type B) is being introduced to be given at same time, but di?erent limb.
4 Known as MMR vaccine. (Some parents are asking to have their infants immunised with single-constituent vaccines because of controversy over possible side-effects – yet to be con?rmed scienti?cally – of the combined MMR vaccine.)
Recommended immunisation schedules in the United Kingdom... immune system
A researcher has suggested a link between the vaccine and AUTISM, but massive studies of children with and without this condition in several countries have failed to ?nd any evidence to back the claim. Nonetheless, the publicity war has been largely lost by the UK health departments so that vaccine rates have dropped to a worryingly low level.
(See IMMUNISATION.)... mmr vaccine
Splenectomy is performed after the spleen has been seriously injured or to treat hypersplenism or certain forms of anaemia.
The absence of the spleen does not normally cause problems; its function is largely taken over by other parts of the lymphatic system and by the liver.
People who have had a splenectomy are more susceptible to certain infections and are given pneumococcal vaccine and long-term antibiotics.... splenectomy
It usually begins at puberty – although young children can be affected – and tends to stop in middle age: in women, for example, attacks often cease after MENOPAUSE. It frequently disappears during pregnancy. The disorder tends to run in families. In susceptible individuals, attacks may be provoked by a wide variety of causes including: anxiety, emotion, depression, shock, and excitement; physical and mental fatigue; prolonged focusing on computer, television or cinema screens; noise, especially loud and high-pitched sounds; certain foods – such as chocolate, cheese, citrus fruits, pastry; alcohol; prolonged lack of food; irregular meals; menstruation and the pre-menstrual period.
Anything that can provoke a headache in the ordinary individual can probably precipitate an attack in a migrainous subject. It seems as if there is an inherited predispostion that triggers a mechanism whereby in the migrainous subject, the headache and the associated sickness persist for hours, a whole day or even longer.
The precise cause is not known, but the generally accepted view is that in susceptible individuals, one or other of these causes produces spasm or constriction of the blood vessels of the brain. This in turn is followed by dilatation of these blood vessels which also become more permeable and so allow ?uid to pass out into the surrounding tissues. This combination of dilatation and outpouring of ?uid is held to be responsible for the headache.
Two types of migraine have been recognised: classical and common. The former is relatively rare and the headache is preceded by a slowly extending area of blindness in one or both eyes, usually accompanied by intermittent ‘lights’. The phenomenon lasts for up to 30 minutes and is followed by a bad, often unilateral headache with nausea, sometimes vomiting and sensitivity to light. Occasionally, passing neurological symptoms such as weakness in a limb may accompany the attack. The common variety has similar but less severe symptoms. It consists of an intense headache, usually situated over one or other eye. The headache is usually preceded by a feeling of sickness and disturbance of sight. In 15–20 per cent of cases this disturbance of sight takes the form of bright lights: the so-called AURA of migraine. The majority of attacks are accompanied by vomiting. The duration of the headache varies, but in the more severe cases the victim is usually con?ned to bed for 24 hours.
Treatment consists, in the ?rst place, of trying to avoid any precipitating factor. Patients must ?nd out which drug, or drugs, give them most relief, and they must always carry these about with them wherever they go. This is because it is a not uncommon experience to be aware of an attack coming on and to ?nd that there is a critical quarter of an hour or so during which the tablets are e?ective. If not taken within this period, they may be ine?ective and the unfortunate victim ?nds him or herself prostrate with headache and vomiting. In addition, sufferers should immediately lie down; at this stage a few hours’ rest may prevent the development of a full attack.
When an attack is fully developed, rest in bed in a quiet, darkened room is essential; any loud noise or bright light intensi?es the headache or sickness. The less food that is taken during an attack the better, provided that the individual drinks as much ?uid as he or she wants. Group therapy, in which groups of around ten migrainous subjects learn how to relax, is often of help in more severe cases, whilst in others the injection of a local anaesthetic into tender spots in the scalp reduces the number of attacks. Drug treatment can be e?ective and those a?icted by migraine may ?nd a particular drug or combination of drugs more suitable than others. ANALGESICS such as PARACETAMOL, aspirin and CODEINE phosphate sometimes help. A combination of buclizine hydrochloride and analgesics, taken when the visual aura occurs, prevents or diminishes the severity of an attack in some people. A commonly used remedy for the condition is ergotamine tartrate, which causes the dilated blood vessels to contract, but this must only be taken under medical supervision. In many cases METOCLOPRAMIDE (an antiemetic), followed ten minutes later by three tablets of either aspirin or paracetamol, is e?ective if taken early in an attack. In milder attacks, aspirin, with or without codeine and paracetamol, may be of value. SUMATRIPTAN (5-hydroxytryptamine [5HT1] AGONIST – also known as a SEROTONIN agonist) is of value for acute attacks. It is used orally or by subcutaneous injection, but should not be used for patients with ischaemic heart disease. Naratriptan is another 5HT1 agonist that is an e?ective treatment for acute attacks; others are almotriptan, rizariptan and zolmitriptan. Some patients ?nd beta blockers such as propranolol a valuable prophylactic.
People with migraine and their relatives can obtain help and guidance from the Migraine Action Association.... migraine
Pneumonia with no predisposing cause – community-acquired pneumonia – is caused most often by Streptococcus pneumoniae (PNEUMOCOCCUS). The other most common causes are viruses, Mycoplasma pneumoniae and Legionella species (Legionnaire’s disease). Another cause, Chlamydia psittaci, may be associated with exposure to perching birds.
In patients with underlying lung disease, such as CHRONIC OBSTRUCTIVE PULMONARY DISEASE (COPD) or BRONCHIECTASIS as in CYSTIC FIBROSIS, other organisms such as Haemophilus in?uenzae, Klebsiella, Escherichia coli and Pseudomonas aeruginosa are more prominent. In patients in hospital with severe underlying disease, pneumonia, often caused by gram-negative bacteria (see GRAM’S STAIN), is commonly the terminal event.
In patients with an immune system suppressed by pregnancy and labour, infection with HIV, CHEMOTHERAPY or immunosuppressive drugs after organ transplantation, a wider range of opportunistic organisms needs to be considered. Some of these organisms such as CYTOMEGALOVIRUS (CMV) or the fungus Pneumocystis carinii rarely cause disease in immunocompetent individuals – those whose body’s immune (defence) system is e?ective.
TUBERCULOSIS is another cause of pneumonia, although the pattern of lung involvement and the more chronic course usually di?erentiate it from other causes of pneumonia.
Symptoms The common symptoms of pneumonia are cough, fever (sometimes with RIGOR), pleuritic chest pain (see PLEURISY) and shortness of breath. SPUTUM may not be present at ?rst but later may be purulent or reddish (rusty).
Examination of the chest may show the typical signs of consolidation of an area of lung. The solid lung in which the alveoli are ?lled with in?ammatory exudate is dull to percussion but transmits sounds better than air-containing lung, giving rise to the signs of bronchial breathing and increased conduction of voice sounds to the stethoscope or palpating hand.
The chest X-ray in pneumonia shows opacities corresponding to the consolidated lung. This may have a lobar distribution ?tting with limitation to one area of the lung, or have a less con?uent scattered distribution in bronchopneumonia. Blood tests usually show a raised white cell (LEUCOCYTES) count. The organism responsible for the pneumonia can often be identi?ed from culture of the sputum or the blood, or from blood tests for the speci?c ANTIBODIES produced in response to the infection.
Treatment The treatment of pneumonia involves appropriate antibiotics together with oxygen, pain relief and management of any complications that may arise. When treatment is started, the causative organism has often not been identi?ed so that the antibiotic choice is made on the basis of the clinical features, prevalent organisms and their sensitivities. In severe cases of community-acquired pneumonia (see above), this will often be a PENICILLIN or one of the CEPHALOSPORINS to cover Strep. pneumoniae together with a macrolide such as ERYTHROMYCIN. Pleuritic pain will need analgesia to allow deep breathing and coughing; oxygen may be needed as judged by the oxygen saturation or blood gas measurement.
Possible complications of pneumonia are local changes such as lung abscess, pleural e?usion or EMPYEMA and general problems such as cardiovascular collapse and abnormalities of kidney or liver function. Appropriate treatment should result in complete resolution of the lung changes but some FIBROSIS in the lung may remain. Pneumonia can be a severe illness in previously ?t people and it may take some months to return to full ?tness.... pneumonia
Pathology There are three types of virus, infection spreading by the stools-contaminated hands-mouth route. Children are most susceptible.
One attack usually produces permanent immunity, and second attacks are rare. The virus typically affects the anterior horn cells of the spinal cord, especially those in the lumbar region; the grey matter of the brain stem and cortex may also be damaged.
Vaccination is given to infants at two, three and four months: a booster dose is given at around the age of ?ve. The vaccine contains all three types of polio virus. Two types of vaccine are available: inactivated polio virus (IPV) contains dead virus and is administered by injections; oral polio vaccine (OPV) contains live, harmless strains. The latter is used in the United Kingdom.
Symptoms The incubation period is around 7–14 days, the onset being marked by a mild fever and headache which improves after a few days. In around 85 per cent of infected children there is no further progression, but in some – after approximately one week – the symptoms recur, together with neck sti?ness and signs of meningeal irritation (see MENINGES). Weakness of individual muscle groups is common, and may progress – to a variable extent, depending on the distribution of the virus – to widespread PARALYSIS. Involvement of the diaphragm and intercostal muscles may lead to respiratory failure and rapid death unless arti?cial respiration is provided. Involvement of the cranial nerves and brain may lead to nystagmus (see under EYE, DISORDERS OF), hoarseness and di?culty in swallowing, and CONVULSIONS may occur in young children. The CEREBROSPINAL FLUID shows an early increase in lymphocytes, followed by a rise in protein concentration.
Treatment There is no e?ective drug treatment for the infection. Treatment involves early bed rest, followed by PHYSIOTHERAPY and orthopaedic measures as required. At the onset of respiratory diffculties a TRACHEOSTOMY and arti?cial ventilation should be started. (In the 1950s, when polio epidemics were occurring, respiratory diffculties were treated by placing patients in an ‘iron lung’ – a large, airtight, cylindrical container in which the air pressure was raised and lowered to simulate normal breathing.) In cases of severe paralysis with persistent wasting of the limbs, surgery may be necessary to minimise the resulting disability.... poliomyelitis
While mercury sphygmomanometers are simple, accurate and easily serviced, there is concern about possible mercury toxicity for users, those servicing the devices and the environment. Use of them has already been banned in some European hospitals. Although it may be a few years before they are widely replaced, automated blood-pressure-measuring devices will increasingly be in routine use. A wide variety of ambulatory blood-pressuremeasuring devices are already available and may be ?tted in general practice or hospital settings, where the patient is advised on the technique. Blood-pressure readings can be taken half-hourly – or more often, if required – with little disturbance of the patient’s daily activities or sleep. (See also BLOOD PRESSURE; HYPERTENSION.)... sphygmomanometer
Alternatives:– Teas. Gotu Kola, Red clover flowers, Chickweed. Singly or in combination. 1 heaped teaspoon to each cup boiling water: infuse 5-10 minutes. 1 cup thrice daily.
Decoction. Fine cut: Burdock 2; Horsetail 1; Echinacea 1; Thuja quarter. Mix. 1oz to 1 pint water gently simmered 15 minutes. Wineglassful (or half a cup) thrice daily, before meals.
Tablets/capsules. Echinacea, Poke root, Prickly Ash bark.
Powders. Formula. Sarsaparilla 1; Echinacea 1; Boneset half; Thuja quarter. Dose: 500mg (two 00 capsules or one-third teaspoon) thrice daily.
Liquid extracts. Formula. Equal parts: Echinacea, Devil’s Claw, Gotu Kola. Dose: 30-60 drops thrice daily before meals.
Tinctures. Formula. Burdock 2; Echinacea 1; Boneset 1; Sarsaparilla 1; Thuja quarter. Fennel quarter. Mix. Dose: 1-2 teaspoons thrice daily.
Cod Liver oil.
Topical. Comfrey poultice, Chickweed cream, Oils of Mullein, Jojoba or Evening Primrose.
Diet. Oily fish (or fish oils). Low salt, low fat.
Supplements. Vitamins A, B-complex, C, D, E, Magnesium, Sulphur, Zinc. ... arthritis – psoriatic
– an early graded return to activity gives the best long-term results, but doing too much too soon runs the risk of exacerbating the original injury.
Chronic (overuse) injuries affecting the bones (see BONE), tendons (see TENDON) or BURSAE of the JOINTS are common in many sports. Examples include chronic INFLAMMATION of the common extensor tendon where it
attaches to the later EPICONDYLE of the humerus – common in throwers and racquet sportspeople – and stress fractures of the TIBIA or METATARSAL BONES of the foot in runners. After an initial period of rest, management often involves coaching that enables the athlete to perform the repetitive movement in a less injury-susceptible manner.
Exercise physiology is the science of measuring athletic performance and physical ?tness for exercise. This knowledge is applied to devising and supervising training regimens based on scienti?c principles. Physical ?tness depends upon the rate at which the body can deliver oxygen to the muscles, known as the VO2max, which is technically di?cult to measure. The PULSE rate during and after a bout of exercise serves as a good proxy of this measurement.
Regulation of sport Sports medicine’s role is to minimise hazards for participants by, for example, framing rule-changes which forbid collapsing the scrum, which has reduced the risk of neck injury in rugby; and in the detection of the use of drugs taken to enhance athletic performance. Such attempts to gain an edge in competition undermine the sporting ideal and are banned by leading sports regulatory bodies. The Olympic Movement Anti-Doping Code lists prohibited substances and methods that could be used to enhance performance. These include some prohibited in certain circumstances as well as those completely banned. The latter include:
stimulants such as AMPHETAMINES, bromantan, ca?eine, carphedon, COCAINE, EPHEDRINE and certain beta-2 agonists.
NARCOTICS such as DIAMORPHINE (heroin), MORPHINE, METHADONE HYDROCHLORIDE and PETHIDINE HYDROCHLORIDE.
ANABOLIC STEROIDS such as methandione, NANDROLONE, stanazol, TESTOSTERONE, clenbuterol, androstenedone and certain beta-2 agonists.
peptide HORMONES, mimetics and analogues such as GROWTH HORMONE, CORTICOTROPHIN, CHORIONIC GONADOTROPHIC HORMONE, pituitary and synthetic GONADOTROPHINS, ERYTHROPOIETIN and INSULIN. (The list produced above is not comprehen
sive: full details are available from the governing bodies of relevant sports.) Among banned methods are blood doping (pre-competition administration of an athlete’s own previously provided and stored blood), administration of arti?cial oxygen carriers or plasma expanders. Also forbidden is any pharmacological, chemical or physical manipulation to affect the results of authorised testing.
Drug use can be detected by analysis of the URINE, but testing only at the time of competition is unlikely to detect drug use designed to enhance early-season training; hence random testing of competitive athletes is also used.
The increasing professionalism and competitiveness (among amateurs and juveniles as well as professionals) in sports sometimes results in pressures on participants to get ?t quickly after injury or illness. This can lead to
players returning to their activity before they are properly ?t – sometimes by using physical or pharmaceutical aids. This practice can adversely affect their long-term physical capabilities and perhaps their general health.... sports medicine
Life is our most precious gift. But at some point that gift might be at risk. It is at such time that food and drink may contribute to our sense of well-being.
Rapidly accumulating evidence links cancer to a growing public awareness of the role of diet. Also, involvement of supplements in cancer prevention are a fruitful area of research.
Vital food enzymes are not destroyed in cooking when a large proportion of food is eaten raw. All food should be free from additives.
A high fat intake is a risk factor in cancer of the ovary, womb and prostate gland. It also affects the bowel flora, changing bile acid metabolism and the concentration of carcinogenic bile acid metabolites. Obesity significantly increases risk of cancer.
Epidemiological studies in man show that people with low Vitamin A levels are more susceptible to lung cancer. Cancer risk is increased by low levels of Vitamin A, particularly Beta Carotene, Vitamin E and Selenium.
Antioxidants control the activity of free-radicals that destroy body cells, and source foods containing them are therefore of value in cancer prevention. Most cancers generate a high degree of toxicity and this is where antioxidants, particularly Vitamin C are indicated. A deficiency of Vitamin C has been associated with cancer of the oesophagus, stomach, lungs and breast. This vitamin is known to increase life expectancy in terminally ill patients and is a mild analgesic for pain. Vitamin B6 may be of value for nausea.
Vitamins and minerals of value: Vitamins A, B6, C, E, Calcium, Chromium, Magnesium, Molybdenum, Selenium, Zinc.
Stimulants should be avoided: cocoa, alcohol, sugar, coffee (including decaffeinated). Tea should not be too strong as it inhibits absorption of iron. Choice should be over a wide range of foods, to eat less fat and more wholegrain cereals and raw fresh fruit and vegetables. ... diet - cancer
Constituents: oestrogens, volatile oil, resin.
Action: sedative, sustaining nervine, hypnotic, mild analgesic, spasmolytic on smooth muscle, bitter, tonic, astringent, antimicrobial (externally), liver and gall bladder relaxant, anaphrodisiac, diuretic.
Uses: Nervous anxiety, hysteria, nervous diarrhoea, nervous stomach, Crohn’s disease, intestinal cramps, nervous bladder, insomnia, neuralgia, excessive sexual excitability. Loss of appetite, menopause, restless legs.
Chinese medicine – tuberculosis of the lungs.
“Of value in cancer.” (J.L. Hartwell, Lloydia, 33, 97, 1970)
Combination. Combines well with Passion flower and Valerian.
Preparations: Average dose: half-1 gram. Thrice daily.
Tea. 1 teaspoon to each cup boiling water; infuse 15 minutes. Dose: half cup.
Liquid Extract: 0.5-1ml.
Tincture BHC Vol 1. One part to 5 parts 60 per cent ethanol. Dose: 1-2ml.
Popular tablet/capsule: powdered Hops BHP (1983) 45mg; powdered Passiflora BHP (1983) 100mg; powdered Extract Valerian 5:1 20mg. For minor stresses and strains, irritability and nervous headaches. For over-activity of children over 12 years. (Gerard House)
Diet: young shoots cooked as Asparagus.
Hop pillow: for healthful sleep.
Fresh Hops require careful handling on drying to prevent loss of pollen. May cause an allergic dermatitis in those susceptible.
Contra-indication: depression.
Powder. 250mg. One 00 capsule or one-sixth teaspoon. ... hops
Healthy people are inoculated with vaccine as a protection against a particular disease; this produces ANTIBODIES which will confer immunity against a subsequent attack of the disease. (See IMMUNISATION for programme of immunisation during childhood.)
Vaccines may be divided into two classes: stock vaccines, prepared from micro-organisms known to cause a particular disease and kept in readiness for use against that disease; and autogenous vaccines, prepared from microorganisms which are already in the patient’s body and to which the disease is due. Vaccines intended to protect against the onset of disease are of the former variety.
Autogenous vaccines are prepared by cultivating bacteria found in SPUTUM, URINE and FAECES, and in areas of in?ammation such as BOILS (FURUNCULOSIS). This type of vaccine was introduced by Wright about 1903.
Anthrax vaccine was introduced in 1882 for the protection of sheep and cattle against this disease. A safe and e?ective vaccine for use in human beings has now been evolved. (See ANTHRAX.)
BCG vaccine is used to provide protection against TUBERCULOSIS. (See also separate entry on BCG VACCINE.)
Cholera vaccine was introduced in India about 1894. Two injections are given at an interval of at least a week; this gives a varying degree of immunity for six months. (See CHOLERA.)
Diphtheria vaccine is available in several forms. It is usually given along with tetanus and pertussis vaccine (see below) in what is known as TRIPLE VACCINE. This is given in three doses: the ?rst at the age of two months; the second at three months; and the third at four months, with a booster dose at the age of ?ve years. (See DIPHTHERIA.)
Hay fever vaccine is a vaccine prepared from the pollen of various grasses. It is used in gradually increasing doses for prevention of HAY FEVER in those susceptible to this condition.
In?uenza vaccine A vaccine is now available for protection against INFLUENZA due to the in?uenza viruses A and B. Its use in Britain is customarily based on advice from the health departments according to the type of in?uenza expected in a particular year.
Measles, mumps and rubella (MMR) vaccines are given in combination early in the second year of life. A booster dose may prove necessary, as there is some interference between this vaccine and the most recent form of pertussis vaccine (see below) o?ered to children. Uptake has declined a little because of media reports suggesting a link with AUTISM – for which no reliable medical evidence (and much to the contrary) has been found by investigating epidemiologists. (See also separate entry for each disease, and for MMR VACCINE.)
Pertussis (whooping-cough) vaccine is prepared from Bordetella pertussis, and is usually given along with diphtheria and tetanus in what is known as triple vaccine. (See also WHOOPING-COUGH.)
Plague vaccine was introduced by Ha?kine, and appears to give useful protection, but the duration of protection is relatively short: from two to 20 months. Two injections are given at an interval of four weeks. A reinforcing dose should be given annually to anyone exposed to PLAGUE.
Poliomyelitis vaccine gives a high degree of protection against the disease. This is given in the form of attenuated Sabin vaccine which is taken by mouth – a few drops on a lump of sugar. Reinforcing doses of polio vaccine are recommended on school entry, on leaving school, and on travel abroad to countries where POLIOMYELITIS is ENDEMIC.
Rabies vaccine was introduced by Pasteur in 1885 for administration, during the long incubation period, to people bitten by a mad dog, in order to prevent the disease from developing. (See RABIES.)
Rubella vaccine, usually given with mumps and measles vaccine in one dose – called MMR VACCINE, see also above – now provides protection against RUBELLA (German measles). It also provides immunity for adolescent girls who have not had the disease in childhood and so ensures that they will not acquire the disease during any subsequent pregnancy – thus reducing the number of congenitally abnormal children whose abnormality is the result of their being infected with rubella via their mothers before they were born.
Smallpox vaccine was the ?rst introduced. As a result of the World Health Organisation’s successful smallpox eradication campaign – it declared the disease eradicated in 1980 – there is now no medical justi?cation for smallpox vaccination. Recently, however, there has been increased interest in the subject because of the potential threat from bioterrorism. (See also VACCINATION.)
Tetanus vaccine is given in two forms: (1) In the so-called triple vaccine, combined with diphtheria and pertussis (whooping-cough) vaccine for the routine immunisation of children (see above). (2) By itself to adults who have not been immunised in childhood and who are particularly exposed to the risk of TETANUS, such as soldiers and agricultural workers.
Typhoid vaccine was introduced by Wright and Semple for the protection of troops in the South African War and in India. TAB vaccine, containing Salmonella typhi (the causative organism of typhoid fever – see ENTERIC FEVER) and Salmonella paratyphi A and B (the organisms of paratyphoid fever – see ENTERIC FEVER) has now been replaced by typhoid monovalent vaccine, containing only S. typhi. The change has been made because the monovalent vaccine is less likely to produce painful arms and general malaise, and there is no evidence that the TAB vaccine gave any protection against paratyphoid fever. Two doses are given at an interval of 4–6 weeks, and give protection for 1–3 years.... vaccine
Symptoms: malaise, bloody alternating diarrhoea and constipation; right side colicky abdominal pain worse after meals; flatulence, loss of weight and appetite. Intestinal obstruction can usually be palpated. Blood count. A blood count high in whites indicates an abscess – a serious condition which may require surgical repair during which segments of the gut may have to be removed. Malignant change rare. Differential diagnosis. Ulcerative colitis, appendicitis, appendix abscess, irritable bowel syndrome.
Cracks or ulcers at corners of the mouth may be a good marker of Crohn’s Disease.
Treatment. Select one of the following. Herbal treatment offers a safe alternative to steroids by inducing remission in acute exacerbation. Good responses have been observed from the anti-bacterials Wild Yam and Goldenseal. Fenugreek seeds are of special value. Comfrey (tissue regeneration). Irish Moss.
Teas: Chamomile, Comfrey leaves, Hops, Marshmallow leaves, Meadowsweet, Shepherd’s Purse (Dr A. Vogel), Lobelia. Silverweed and Cranesbill are excellent for internal bleeding; Poke root for intestinal ulceration.
Decoction. Fenugreek seeds: 2 teaspoons to large cup water simmered gently 10 minutes. 1 cup freely. The seeds also should be consumed.
Tablets/capsules. Wild Yam, Fenugreek, Ginger, Goldenseal, Lobelia, Slippery Elm.
Powders. Formula. Wild Yam 2; Meadowsweet 2; Goldenseal 1. Dose: 500mg (two 00 capsules or one- third teaspoon) thrice daily.
Liquid Extracts. (1) Formula. Wild Yam 1, Echinacea 2. 30-60 drops in water thrice daily. Or, (2) Formula: Turkey Rhubarb 2, Goldenseal 1, Caraway half. 20-30 drops in water thrice daily.
Tinctures. Formula. Bayberry 2, Goldenseal 1, Cardamoms 1. Dose: One to two 5ml teaspoons thrice daily.
Ispaghula seeds. 2-4 teaspoons thrice daily.
Tea Tree oil Suppositories. Insertion at night.
Diet. Bland, little fibre, Slippery Elm gruel. Irish Moss preparations. Increase fluid intake. Reject: broccoli, tomatoes, lima, Soya, Brussels sprouts, pinto beans, cocoa, chocolate, cow’s milk, peas, onions, turnips, radishes. Accept fish oils.
Addenbrookes Hospital, Cambridge. Reject foods containing wheat and all dairy produce.
Supplements. Vitamins A, B12, C, Calcium, Iron, Magnesium, Potassium, Zinc.
Study. In a study carried out by UK researchers (1993) food allergies were found to be the most common cause of the disease. Results suggested that dietary changes may be as effective as corticosteroids in easing symptoms. The most common allergens were corn, wheat, milk, yeast, egg, potato, rye, tea, coffee, apples, mushrooms, oats, chocolate. An elemental diet with a formula of nutrients (E028, produced by Hospital Supplies, Liverpool) was used in trials. (The Lancet, 6.11.1993)
Notes. Crohn’s Disease is associated with Erythema nodosum, more frequently recognised in childhood. A frequent cause is cow’s milk intolerance. Smoking adds to the risk of Crohn’s disease.
In susceptible people, the food additives titanium dioxide and aluminosilicates may evoke a latent inflammatory response resulting in Crohn’s disease, ulcerative colitis or bowel cancer. These chemicals may be found in the intestinal lymphoid aggregations in gut mucosa. (Jonathan Powell, Gastro-intestinal Laboratory, St Thomas’s Hospital, London) (Titanium dioxide rarely occurs naturally but is added to confectionery, drinking water and anti-caking agents.) ... crohn’s disease
Symptoms. Upper abdominal pain, fever, nausea, backache, low blood pressure, high white cell count. Tre atme nt: anti-inflammatories, herbal antibiotics for bacterial infection. Allspice, Bearberry, Elecampane, Goldenseal, Liquorice root, Mullein, Nettles, Wahoo. Others as follows:–
Teas: Haronga Tree, Chamomile, Mullein, Uva Ursi, Burdock leaves, Marigold petals, Liquorice. Cup every 3 hours.
Decoctions: Sarsaparilla (hot). Barberry (cold). See: DECOCTION.
Tablets/capsules. Blue Flag root, Chamomile, Sarsaparilla, Kelp.
Formula. Echinacea 2; Blue Flag root 1; Liquorice root 1. Dose – Liquid extracts: 1 teaspoon. Tinctures: 2 teaspoons. Powders: 500mg (two 00 capsules or one-third teaspoon); every 3 hours for acute cases, otherwise thrice daily.
Goldenseal, tincture: 10 drops once daily maintenance prophylactic dose.
External. Poultice over upper abdomen: Mullein, Chamomile or Castor oil.
Diet. Abundant citrus fruits.
Supplements. Vitamin C, methionine and selenium to mop up free radicals. Without the supplements toxins strike the pancreas, leading to severe pain. In this way they can be used as an alternative to pain-killers. (Researchers, Manchester Royal Infirmary)
Vitamin C. Lack of Vitamin C may trigger acute pancreatitis in susceptible patients. (Mr Patrick Scott, Manchester Royal Infirmary) ... pancreatitis
Symptoms. Spastic colon: colon held in spasm. The two main symptoms are abdominal pain and altered bowel habit. Pain relieved on going to stool or on passing wind. Diarrhoea with watery stools on rising may alternate with constipation. Sensation that the bowel is incompletely emptied. Flatulence. Passing of mucus between stools. The chronic condition may cause anaemia, weight loss and rectal blood calling for treatment of the underlying condition.
Indicated: astringents, demulcents, antispasmodics.
Treatment. If possible, start with 3-day fast.
Alternatives. Teas. (1) Combine equal parts; Agrimony (astringent), Hops (colon analgesic), Ephedra (anti-sensitive). (2) Combine equal parts; Meadowsweet (astringent) and German Chamomile (nervine and anti-inflammatory). Dose: 1 heaped teaspoon to each cup boiling water; infuse 15 minutes. 1 cup freely, as tolerated. Bilberry tea. 2 tablespoons fresh or dried Bilberries in 1 pint water simmered 10 minutes. Half-1 cup freely.
Note: Old European: Chamomile and Caraway seed tea. 1 cup morning and evening.
Decoction. Formula. Tormentil root 2; Bistort root 2; Valerian root 1. Dose: 2 teaspoons to each cup water simmered 20 minutes. Half-1 cup 3-4 times daily.
Tablets/capsules. Calamus. Cramp bark. Goldenseal. Slippery Elm, Cranesbill.
Formula. Cranesbill 2; Caraway 2; Valerian half. Dose: Powders: 750mg or half a teaspoon). Liquid Extracts: 1-2 teaspoons. Tinctures: 2-4 teaspoons. Thrice daily.
Practitioner. RX tea: equal parts herbs Peppermint, Balm and German Chamomile. Infuse 1-2 teaspoons in cup boiling water and add 3 drops Tincture Belladonna.
Formula. Tinctures. Black Catechu 2; Cranesbill 1; Hops quarter. Dose: 1-2 teaspoons in water or honey, thrice daily.
Psyllium seeds (Ispaghula). 2-5 teaspoons taken with sips of water, or as Normacol, Isogel, etc. For pain in bowel, Valerian.
Fenugreek seeds. 2 teaspoons to cup water simmered 10 minutes. Half-1 cup freely. Consume seeds. Cinnamon, tincture or essence: 30-60 drops in water 3-4 times daily.
Menstrual related irritable bowel. Evening Primrose.
Irritable Bowel Syndrome, with neurosis. Treat thyroid gland (Bugleweed, Kelp, etc).
With severe nerve stress: add CNS (central nervous system) relaxant (Hops, Ladies Slipper, Roman Chamomile)
Oil of Peppermint. A simple alternative. 3-5 drops in teaspoon honey, or in enteric-coated capsule containing 0.2ml standardised Peppermint oil B.P., (Ph.Eur.)
Intestinal antispasmodics: Valerian, Chamomile, Balm, Rosemary.
Diet. “People with IBS should stop drinking coffee as it can induce a desire to defecate.” (Hallamshire Hospital Research Team)
Dandelion coffee. Fenugreek tea. Carrot juice. Bananas mashed into a puree with Slippery Elm powder. Yoghurt. Gluten-free diet.
Supplements. Calcium lactate tablets: 2 × 300mg thrice daily at meals. Floradix. Lactobacillus acidophilus to counteract toxic bacteria. Vitamin C (2-4g). Zinc. Linusit.
Note: Serious depression may underlay the condition. Anti-depressants sometimes relieve symptoms dramatically.
Chronic cases. Referral to Gastrology Outpatient Department. ... irritable bowel syndrome (ibs)
Three causative factors interact in the development of the illness: personality, environment, and the addictive nature of alcohol. Inadequate, insecure, or immature personalities are more at risk. Environmental factors are important, especially the ready availability, affordability, and social acceptance of alcohol. Genetic factors may play a part in causing dependence in some cases, but it is now widely believed that anyone, irrespective of personality, environment, or genetic background, can become an alcoholic. Stress is often a major factor in precipitating heavy drinking.
Alcohol dependence usually develops in 4 main stages that occur over a number of years. In the 1st phase, tolerance to alcohol develops in the heavy social drinker. In the 2nd phase, the drinker experiences memory lapses relating to events during the drinking episodes. In the 3rd phase, there is loss of control over alcohol consumption. The final phase is characterized by prolonged binges of intoxication and mental or physical complications.
Behavioural symptoms are varied and can include furtive, aggressive, or grandiose behaviour; personality changes (such as irritability, jealousy, or uncontrolled anger); neglect of food intake and personal appearance; and lengthy periods of intoxication.
Physical symptoms may include nausea, vomiting, or shaking in the morning; abdominal pain; cramps; numbness or tingling; weakness in the legs and hands; irregular pulse; enlarged blood vessels in the face; unsteadiness; confusion; memory lapses; and incontinence. After sudden withdrawal from alcohol, delirium tremens may occur.
Alcohol-dependent persons are more susceptible than others to a variety of physical and mental disorders (see alcohol-related disorders).
Many alcoholics require detoxification followed by long-term treatment. Different methods of treatment may be combined. Psychological treatments involve psychotherapy and are commonly carried out as group therapy. Social treatments may offer practical help and tend to include family members in the process. Physical treatment generally includes the use of disulfiram, a drug that sensitizes the drinker to alcohol so that he or she experiences unpleasant side effects when drinking. Alcoholics Anonymous and other self-help organizations can provide support and advice.... alcohol dependence
condition that causes inflammation in the joints and other body tissues such as the membranous heart covering, lungs, and eyes. The disorder has different effects in children (see juvenile chronic arthritis). Ankylosing spondylitis is another persistent form of arthritis that initially affects the spine and the joints between the base of the spine and the pelvis. Other tissues, such as the eyes, may also be affected. Eventually, the disorder may cause the vertebrae (bones of the spine) to fuse. Reactive arthritis typically develops in susceptible people following an infection, most commonly of the genital tract or intestines. Gout and pseudogout are types of arthritis in which crystals are deposited in a joint, causing swelling and pain. Septic arthritis is a relatively rare condition that can develop when infection enters a joint either through a wound or from the bloodstream.
Diagnosis of particular types of arthritis is made from blood tests and, in some cases, microscopic examination of fluid from the affected joint. X-rays or MRI can indicate the type and extent of joint damage.
Physiotherapy and exercises can help to minimize the effects of arthritis, and there are specific treatments for some types, such as antibiotic drugs for septic arthritis.
In severe cases, one or more joints may need arthroplasty (replacement with an artificial substitute) or arthrodesis (fusion of the bones).... arthritis
During an asthma attack, the muscle in the walls of the airways contracts, causing narrowing. The linings of the airways also become swollen and inflamed, producing excess mucus that can block the smaller airways.
In some people, an allergic response triggers the airway changes. This allergic type of asthma tends to occur in
childhood and may develop in association with eczema or certain other allergic conditions such as hay fever (see rhinitis, allergic). Susceptibility to these conditions frequently runs in families and may be inherited.
Some substances, called allergens, are known to trigger attacks of allergic asthma. They include pollen, house-dust mites, mould, and dander and saliva from furry animals such as cats and dogs. Rarely, certain foods, such as milk, eggs, nuts, and wheat, provoke an allergic asthmatic reaction. Some people with asthma are sensitive to aspirin, and taking it may trigger an attack.
When asthma starts in adulthood, there are usually no identifiable allergic triggers. The 1st attack is sometimes brought on by a respiratory infection.
Factors that can provoke attacks in a person with asthma include cold air, exercise, smoke, and occasionally emotional factors such as stress and anxiety. Although industrial pollution and exhaust emission from motor vehicles do not normally cause asthma, they do appear to worsen symptoms in people who already have the disorder. Pollution in the atmosphere may also trigger asthma in susceptible people.
In some cases, a substance that is inhaled regularly in the work environment can cause a previously healthy person to develop asthma. This type is called occupation asthma and is one of the few occupational lung diseases that is still increasing in incidence.
There are currently about 200 substances used in the workplace that are known to trigger symptoms of asthma, including glues, resins, latex, and some chemicals, especially isocyanate chemicals used in spray painting. However, occupational asthma can be difficult to diagnose because a person may be regularly exposed to a particular trigger substance for weeks, months, or even years before the symptoms of asthma begin to appear.
Asthmatic attacks can vary in severity from mild breathlessness to respiratory failure. The main symptoms are wheezing, breathlessness, dry cough, and tightness in the chest. In a severe attack, breathing becomes increasingly difficult, resulting in a low level of oxygen in the blood. This causes cyanosis (bluish discoloration) of the face, particularly the lips. Untreated, such attacks may be fatal.
There is no cure for asthma, but attacks can be prevented to a large extent if a particular allergen can be identified.
Treatment involves inhaled bronchodilator drugs (sometimes known as relievers) to relieve symptoms. When symptoms occur frequently, or are severe, inhaled corticosteroids are also prescribed. These drugs are used continuously to prevent attacks by reducing inflammation in the airways and are also known as preventers.
Other drug treatments include sodium cromoglicate and nedocromil sodium, which are useful in preventing exerciseinduced asthma.
A new group of drugs called leukotriene receptor antagonists may reduce the dose of corticosteroid needed to control the condition.
Theophylline or the inhaled anticholinergic drug ipratropium may also be used as bronchodilators.
An asthma attack that has not responded to treatment with a bronchodilator needs immediate assessment and treatment in hospital.... asthma
such as iritis (inflammation of the iris) and corneal ulcer. It is also used in children before eye examination. Atropine may be included in a premedication before general anaesthesia to reduce respiratory secretions and is also used as an emergency treatment for bradycardia (abnormally slow heartbeat). It is sometimes combined with an antidiarrhoeal drug to relieve abdominal cramps accompanying diarrhoea.
Adverse effects include dry mouth, blurred vision, retention of urine, and, in the elderly, confusion.
Atropine eyedrops are rarely given to adults because they cause disturbance of vision lasting 2–3 weeks and may precipitate acute glaucoma in susceptible people.... atropine
The brainstem is composed of 3 main parts: the midbrain, pons, and medulla. The midbrain contains the nuclei (nervecell centres) of the 3rd and 4th cranial nerves. It also contains cell groups involved in smooth coordination of limb movements. The pons contains nerve fibres that connect with the cerebellum. It also houses the nuclei for the 5th–8th cranial nerves. The medulla contains the nuclei of the 9th–12th cranial nerves. It also contains the “vital centres” (groups of nerve cells that regulate the heartbeat, breathing, blood pressure, and digestion (information on which is relayed via the 10th cranial nerve (see vagus nerve). Nerve-cell groups in the brainstem, known collectively as the reticular formation, alert the higher brain centres to sensory stimuli that may require a conscious response. Our sleep/wake cycle is controlled by the reticular formation.
The brainstem is susceptible to the same disorders that afflict the rest of the central nervous system (see brain, disorders of). Damage to the medulla’s vital centres is rapidly fatal; damage to the reticular formation may cause coma. Damage to specific cranial nerve nuclei can sometimes lead to specific effects. For example, damage to the 7th cranial nerve (the facial nerve) leads to facial palsy. Degeneration of the substantia nigra in the midbrain is thought to be a cause of Parkinson’s disease.... brainstem
It is usually due to a viral infection.
Bacterial infection of the airways may occur as a complication.
Smokers, babies, elderly people, and those with lung disease are particularly susceptible.
The main symptoms are wheezing, shortness of breath, and a cough that produces yellow or green sputum.
There may also be pain behind the sternum (breastbone) and fever.
Symptoms may be relieved by drinking plenty of fluids and inhaling steam or using a humidifier.
Most cases clear up without further treatment, but acute bronchitis may be serious in people who already have lung damage.... bronchitis, acute
Causes of cancer include environmental factors such as sunlight, smoking, pollutants, alcohol consumption, and dietary factors. These factors may provoke critical changes in body cells in susceptible people. Susceptibility to certain cancers may be inherited.
Many cancers are now curable, usually by combinations of surgery, radiotherapy, and anticancer drugs. For information on particular cancers, refer to the organ in question (for example lung cancer; stomach cancer).... cancer
The most common cervical infections are sexually transmitted, such as gonorrhoea, chlamydial infections, and trichomoniasis.
Viral infections of the cervix include those due to the human papilloma virus and the herpes simplex virus (see warts, genital; herpes, genital).
Polyps are noncancerous growths on the cervix.
Cancerous growths (see cervix, cancer of) are preceded by changes in the surface cells (cervical dysplasias), which can be detected by a cervical smear test.... cervix, disorders of
of the brain or nervous system, or children with a family history of epilepsy.... convulsion, febrile
Cystitis is common in women because the urethra is short, making it easier for bacteria to pass into the bladder. A bladder calculus (stone), a bladder tumour, or a urethral stricture can obstruct urine flow and increase the risk of infection. In men, cystitis is rare; it usually occurs when an obstruction, such as an enslarged prostate gland (see prostate, enlarged), compresses the urethra. Cystitis is children is often associated with a structural abnormality of the ureters, which allows reflux (backward flow) of urine. The use of catheters (see catheterization, urinary) also carries the risk of infection. Diabetics are especially susceptible to urinary tract infections.
Symptoms of mild cystitis may be relieved by drinking 1 pint (1?2 liter) of fluid every 4 hours. Any infection is treated with antibiotic drugs.... cystitis
Dehydration occurs due to inadequate intake of fluids or excessive fluid loss. The latter may occur with severe or prolonged vomiting or diarrhoea or with uncontrolled diabetes mellitus, diabetes insipidus, and some types of kidney failure. Children are especially susceptible to dehydration by diarrhoea.
Severe dehydration causes extreme thirst, dry lips and tongue, an increase in heart rate and breathing rate, dizziness, confusion, lethargy, and eventual coma. The skin looks dry and loses its elasticity. Any urine passed is small in quantity and dark-coloured. If there is also salt depletion, there may also be headaches, cramps, and pallor.
Bottled mineral water can help maintain the intake of salts. For vomiting and diarrhoea, rehydration therapy is needed; salt and glucose rehydration mixtures are available from chemists.
In severe cases of dehydration, fluids are given intravenously.
The water/salt balance is carefully monitored by blood tests and adjusted if necessary.... dehydration
People with Down’s syndrome have an extra chromosome (47 instead of 46). Affected individuals have 3 copies of chromosome number 21 instead of 2; the disorder is also called trisomy 21. In most cases, it is the result of a sperm or egg being formed with an extra chromosome 21. If one of these takes part in fertilization, the baby will also have the extra chromosome. This type of abnormality is more likely if the mother is aged over 35. A less common cause is a chromosomal abnormality known as a translocation, in which part of 1 parent’s own chromosome number 21 has joined with another chromosome. The parent is unaffected but has a high risk of having Down’s children.
Typical physical features of a person with Down’s syndrome include small face and features; sloping eyes with folds of skin that cover their inner corners; large tongue; and short, broad hands. People with Down’s syndrome have a greater than normal risk for certain disorders, such as a heart defect at birth (see heart disease, congenital), intestinal atresia (a narrowing in the intestines), congenital deafness, and acute leukaemia. Down’s syndrome children are especially susceptible to ear infections. A type of Alzheimer’s disease often develops after age 40.
Down’s syndrome is usually recognized soon after birth.
The diagnosis is confirmed by chromosome analysis.
Screening tests during early pregnancy, including ultrasound scanning, indicate those fetuses likely to have the syndrome.
Amniocentesis is then offered.... down’s syndrome
Infection is the most common cause of ear disorders; it may occur in the ear canal, leading to otitis externa, or affect the middle ear, causing otitis media. This can lead to perforation of the eardrum (see eardrum, perforated). Persistent glue ear, often due to infection, is the most common cause of childhood hearing difficulties. Viral infection of the inner ear may cause labyrinthitis.
Cauliflower ear is the result of one large or several small injuries to the pinna. Perforation of the eardrum can result from poking objects into the ear or loud noise. Prolonged exposure to loud noise can cause tinnitus and/or deafness. Pressure changes associated with flying or scuba diving can also cause minor damage (see barotrauma).Tumours of the ear are rare. Acoustic neuroma is a noncancerous tumour of the acoustic nerve that may press on structures in the ear to cause deafness, tinnitus, and problems with balance.
In cholesteatoma, skin cells and debris collect in the middle ear. Obstruction of the ear canal is most often the result of earwax, although in small children, an object may have been pushed into the ear (see ear, foreign body in).
In otosclerosis, a hereditary condition, a bone in the middle ear becomes fixed, causing deafness. Meniérè’s disease is an uncommon condition in which deafness, vertigo, and tinnitus result from the accumulation of fluid in the inner ear. Deafness in many elderly people is due to presbyacusis, in which hair cells in the cochlea deteriorate.
Certain drugs, such as aminoglycoside drugs and some diuretic drugs, can damage ear function.... ear, disorders of
Good oral hygiene is the main means of preventing and treating gingivitis.
Untreated, it may damage gum tissue, which may lead to chronic periodontitis.
Acute ulcerative gingivitis may develop in people with chronic gingivitis, especially those with lowered resistance to infection (see gingivitis, acute ulcerative).... gingivitis
The nails are susceptible to damage through injury, or by bacterial or fungal infections, especially tinea and candidiasis. Sometimes they become abnormally thick and curved: a condition known as onychogryphosis. Nail abnormalities may be a sign of skin disease, such as alopecia areata, psoriasis, and lichen planus, or of more generalized disease, for example iron-deficiency anaemia. Unusual nail colour may indicate disease.
Treatment of nail disorders can be difficult. Creams and lotions seldom penetrate sufficiently; oral medication may take months to be effective.... nail
A main function of the nose is to filter, warm, and moisten inhaled air before it passes into the rest of the respiratory tract. Just inside the nostrils, small hairs trap large dust particles and foreign bodies. Smaller dust particles are filtered from the air by the microscopic hairs of the conchae. The mucus on the conchae flows inwards, carrying microorganisms and other foreign bodies back towards the nasopharynx to be swallowed and destroyed in the stomach.
The nose detects smells by means of the olfactory nerve endings, which, when stimulated by inhaled vapours, transmit this information to the olfactory bulb in the brain.
The nose is susceptible to a wide range of disorders. Allergies (see rhinitis, allergic), infections such as colds (see cold, common), and small boils are common. Backward spread of infection from the nose occasionally causes a serious condition called cavernous sinus thrombosis. The nose is also particularly prone to injury (see nosebleed; nose, broken). Obstruction of the nose may be caused by a nasal polyp (a projection of swollen mucous membrane).
Noncancerous tumours of blood vessels, known as haemangiomas, commonly affect the nasal cavity in babies. Basal cell carcinoma and squamous cell carcinoma may occur around the nostril. The nose may also be invaded by cancers originating in the sinuses.... nose
Congenital abnormalities, such as horseshoe kidney, are fairly common and usually harmless. Serious inherited disorders include polycystic kidney disease (see kidney, polycystic), Fanconi’s syndrome, and renal tubular acidosis.
Blood vessels in the kidneys can be damaged by shock, haemolytic–uraemic syndrome, polyarteritis nodosa, diabetes mellitus, and systemic lupus erythematosus. The filtering units may be inflamed (see glomerulonephritis). Allergic reactions to drugs, prolonged treatment with analgesic drugs, and some antibiotics can damage kidney tubules. Noncancerous kidney tumours are rare, as is kidney cancer. Metabolic disorders, such as hyperuricaemia, may cause kidney stones (see calculus, urinary tract). Infection of the kidney is called pyelonephritis. Hydronephrosis is caused by urinary tract obstruction. In crush syndrome, kidney function is disrupted by proteins released into the blood from damaged muscle. Hypertension can be a cause and an effect of kidney damage. The most obvious symptom of acute kidney failure is usually oliguria (reduced volume of urine). This leads to a build-up of urea and other waste products in the blood and tissues, which may cause drowsiness, nausea, and breathlessness. Symptoms of chronic kidney failure develop more gradually and may include nausea, loss of appetite, and weakness. If acute kidney failure is due to sudden reduction in blood flow, blood volume and pressure can be brought back to normal by saline intravenous infusion or blood transfusion. Surgery may be needed to remove an obstruction in the urinary tract. Acute kidney disease may be treated with corticosteroid drugs. Treatment may also involve diuretic drugs and temporary dialysis (artificial purification of the blood). A high-carbohydrate, lowprotein diet with controlled fluid and salt intake is important for both types of kidney failure. Chronic kidney failure may progress over months or years towards end-stage kidney failure, which is life-threatening. At this stage, longterm dialysis or a kidney transplant is the only effective treatment.... kidney disorders
There is no specific treatment. Fractures are immobilized and usually heal quickly, but they may cause shortening and deformity of the limbs, resulting in abnormal, stunted growth. Skull fractures may cause brain damage or death. Parents may have genetic counselling to estimate the risk in future children. Severe cases can be diagnosed prenatally by ultrasound scanning.... osteogenesis imperfecta
Acute otitis media can cause sudden severe earache, a feeling of fullness in the ear, deafness, tinnitus, and fever. The eardrum may burst, in which case healing usually occurs within a few weeks. The condition is diagnosed by examination of the middle ear with an otoscope; the eardrum will appear red and possibly bulging outwards. Treatment is with analgesic drugs, and sometimes antibiotic drugs, although many childhood infections are viral.
One possible complication of otitis media is glue ear (chronic secretory otitis media), in which a thick fluid builds up in the ear and affects hearing.
It may develop following severe or recurrent otitis media, particularly in children.
Other complications include hearing impairment and a cholesteatoma.
In rare cases, the infection responsible for otitis media spreads inwards to cause mastoiditis.... otitis media
Symptoms of salmonella food poisoning usually develop suddenly 12–24 hours after infection and include headache, nausea, abdominal pain, diarrhoea, and sometimes fever. The symptoms usually last for only 2 or 3 days, but, in severe cases, dehydration or septicaemia may develop.
Treatment is by rehydration therapy.
In severe cases, fluid replacement by intravenous infusion may be needed.... salmonella infections
Exposure to sunlight can affect the eyes, causing irritation of the conjunctiva, actinic keratopathy, or pterygium.
Good sunglasses help to prevent eye problems.... sunlight, adverse effects of
For example, vitamin D is used to treat osteomalacia, and vitamin A derivatives are given for severe acne.... vitamin supplements
Wounds can be divided into the following categories: an incised wound; an abrasion (or graze); a laceration; a penetrating wound; and a contusion. wound infection Any type of wound is susceptible to the entry of bacteria; the resultant infection can delay healing, result in disability, and may even cause death. Infection of a wound is indicated by redness, swelling, warmth, pain, and sometimes by the presence of pus or the formation of an abscess. Infection may spread locally to adjacent organs or tissue, or to more distant parts of the body via the blood.
The type of infection depends upon how the wound occurred. For example, wounds brought into contact with soil can result in tetanus. STAPHYLOCOCCI, including MRSA, are also common wound infections.
Once infection is discovered, a sample of blood or pus is taken and the patient is given an antibiotic drug. Any abscess should be drained surgically.... wound
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