Acromegaly Health Dictionary

A drug that stimulates DOPAMINE receptors in the brain. It inhibits production of the hormone PROLACTIN and is used to treat GALACTORRHOEA (excessive milk secretion) and also to suppress normal LACTATION. The drug is helpful in treating premenstrual breast engorgement and also ACROMEGALY.... bromocriptine

A product of the anterior part of the PITUITARY GLAND that promotes normal growth and development in the body by changing the chemical activity in the cells. The hormone activates protein production in the muscle cells as well as the release of energy from the metabolism of fats. Its release is controlled by the contrasting actions of growth-hormone releasing factor and somatostatin. If the body produces too much growth hormone before puberty GIGANTISM results; in adulthood the result is ACROMEGALY. Lack of growth hormone in children retards growth.

For many years growth hormone was extracted from human corpses and very rarely this caused CREUTZFELDT-JAKOB DISEASE (CJD) in the recipients. The hormone is now genetically engineered, so safe.... growth hormone

Excessive growth (mainly in height) caused by overproduction, during childhood or adolescence, of GROWTH HORMONE by a tumour of the PITUITARY GLAND. Untreated, the affected individual may die in early adulthood. Sometimes the tumour appears after the individual has stopped growing and the result then is ACROMEGALY rather than gigantism.... gigantism

Bone is not an inert sca?olding for the human body. It is a living, dynamic organ, being continuously remodelled in response to external mechanical and chemical in?uences and acting as a large reservoir for calcium and phosphate. It is as susceptible to disease as any other organ, but responds in a way rather di?erent from the rest of the body.

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

Diabetes mellitus is a condition characterised by a raised concentration of glucose in the blood due to a de?ciency in the production and/or action of INSULIN, a pancreatic hormone made in special cells called the islet cells of Langerhans.

Insulin-dependent and non-insulindependent diabetes have a varied pathological pattern and are caused by the interaction of several genetic and environmental factors.

Insulin-dependent diabetes mellitus (IDDM) (juvenile-onset diabetes, type 1 diabetes) describes subjects with a severe de?ciency or absence of insulin production. Insulin therapy is essential to prevent KETOSIS – a disturbance of the body’s acid/base balance and an accumulation of ketones in the tissues. The onset is most commonly during childhood, but can occur at any age. Symptoms are acute and weight loss is common.

Non-insulin-dependent diabetes mellitus (NIDDM) (maturity-onset diabetes, type 2 diabetes) may be further sub-divided into obese and non-obese groups. This type usually occurs after the age of 40 years with an insidious onset. Subjects are often overweight and weight loss is uncommon. Ketosis rarely develops. Insulin production is reduced but not absent.

A new hormone has been identi?ed linking obesity to type 2 diabetes. Called resistin – because of its resistance to insulin – it was ?rst found in mice but has since been identi?ed in humans. Researchers in the United States believe that the hormone may, in part, explain how obesity predisposes people to diabetes. Their hypothesis is that a protein in the body’s fat cells triggers insulin resistance around the body. Other research suggests that type 2 diabetes may now be occurring in obese children; this could indicate that children should be eating a more-balanced diet and taking more exercise.

Diabetes associated with other conditions (a) Due to pancreatic disease – for example, chronic pancreatitis (see PANCREAS, DISORDERS OF); (b) secondary to drugs – for example, GLUCOCORTICOIDS (see PANCREAS, DISORDERS OF); (c) excess hormone production

– for example, growth hormone (ACROMEGALY); (d) insulin receptor abnormalities; (e) genetic syndromes (see GENETIC DISORDERS).

Gestational diabetes Diabetes occurring in pregnancy and resolving afterwards.

Aetiology Insulin-dependent diabetes occurs as a result of autoimmune destruction of beta cells within the PANCREAS. Genetic in?uences are important and individuals with certain HLA tissue types (HLA DR3 and HLA DR4) are more at risk; however, the risks associated with the HLA genes are small. If one parent has IDDM, the risk of a child developing IDDM by the age of 25 years is 1·5–2·5 per cent, and the risk of a sibling of an IDDM subject developing diabetes is about 3 per cent.

Non-insulin-dependent diabetes has no HLA association, but the genetic in?uences are much stronger. The risks of developing diabetes vary with di?erent races. Obesity, decreased exercise and ageing increase the risks of disease development. The risk of a sibling of a NIDDM subject developing NIDDM up to the age of 80 years is 30–40 per cent.

Diet Many NIDDM diabetics may be treated with diet alone. For those subjects who are overweight, weight loss is important, although often unsuccessful. A diet high in complex carbohydrate, high in ?bre, low in fat and aiming towards ideal body weight is prescribed. Subjects taking insulin need to eat at regular intervals in relation to their insulin regime and missing meals may result in hypoglycaemia, a lowering of the amount of glucose in the blood, which if untreated can be fatal (see below).

Oral hypoglycaemics are used in the treatment of non-insulin-dependent diabetes in addition to diet, when diet alone fails to control blood-sugar levels. (a) SULPHONYLUREAS act mainly by increasing the production of insulin;

(b) BIGUANIDES, of which only metformin is available, may be used alone or in addition to sulphonylureas. Metformin’s main actions are to lower the production of glucose by the liver and improve its uptake in the peripheral tissues.

Complications The risks of complications increase with duration of disease.

Diabetic hypoglycaemia occurs when amounts of glucose in the blood become low. This may occur in subjects taking sulphonylureas or insulin. Symptoms usually develop when the glucose concentration falls below 2·5 mmol/l. They may, however, occur at higher concentrations in subjects with persistent hyperglycaemia – an excess of glucose – and at lower levels in subjects with persistent hypo-glycaemia. Symptoms include confusion, hunger and sweating, with coma developing if blood-sugar concentrations remain low. Re?ned sugar followed by complex carbohydrate will return the glucose concentration to normal. If the subject is unable to swallow, glucagon may be given intramuscularly or glucose intravenously, followed by oral carbohydrate, once the subject is able to swallow.

Although it has been shown that careful control of the patient’s metabolism prevents late complications in the small blood vessels, the risk of hypoglycaemia is increased and patients need to be well motivated to keep to their dietary and treatment regime. This regime is also very expensive. All risk factors for the patient’s cardiovascular system – not simply controlling hyperglycaemia – may need to be reduced if late complications to the cardiovascular system are to be avoided.

Diabetes is one of the world’s most serious health problems. Recent projections suggest that the disorder will affect nearly 240 million individuals worldwide by 2010 – double its prevalence in 1994. The incidence of insulin-dependent diabetes is rising in young children; they will be liable to develop late complications.

Although there are complications associated with diabetes, many subjects live normal lives and survive to an old age. People with diabetes or their relatives can obtain advice from Diabetes UK (www.diabetes.org.uk).

Increased risks are present of (a) heart disease, (b) peripheral vascular disease, and (c) cerebrovascular disease.

Diabetic eye disease (a) retinopathy, (b) cataract. Regular examination of the fundus enables any abnormalities developing to be detected and treatment given when appropriate to preserve eyesight.

Nephropathy Subjects with diabetes may develop kidney damage which can result in renal failure.

Neuropathy (a) Symmetrical sensory polyneuropathy; damage to the sensory nerves that commonly presents with tingling, numbness of pain in the feet or hands. (b) Asymmetrical motor diabetic neuropathy, presenting as progressive weakness and wasting of the proximal muscles of legs. (c) Mononeuropathy; individual motor or sensory nerves may be affected. (d) Autonomic neuropathy, which affects the autonomic nervous system, has many presentations including IMPOTENCE, diarrhoea or constipation and postural HYPOTENSION.

Skin lesions There are several skin disorders associated with diabetes, including: (a) necrobiosis lipoidica diabeticorum, characterised by one or more yellow atrophic lesions on the legs;

(b) ulcers, which most commonly occur on the feet due to peripheral vascular disease, neuropathy and infection. Foot care is very important.

Diabetic ketoacidosis occurs when there is insu?cient insulin present to prevent KETONE production. This may occur before the diagnosis of IDDM or when insu?cient insulin is being given. The presence of large amounts of ketones in the urine indicates excess ketone production and treatment should be sought immediately. Coma and death may result if the condition is left untreated.

Symptoms Thirst, POLYURIA, GLYCOSURIA, weight loss despite eating, and recurrent infections (e.g. BALANITIS and infections of the VULVA) are the main symptoms.

However, subjects with non-insulindependent diabetes may have the disease for several years without symptoms, and diagnosis is often made incidentally or when presenting with a complication of the disease.

Treatment of diabetes aims to prevent symptoms, restore carbohydrate metabolism to as near normal as possible, and to minimise complications. Concentration of glucose, fructosamine and glycated haemoglobin in the blood are used to give an indication of blood-glucose control.

Insulin-dependent diabetes requires insulin for treatment. Non-insulin-dependent diabetes may be treated with diet, oral HYPOGLYCAEMIC AGENTS or insulin.

Insulin All insulin is injected – mainly by syringe but sometimes by insulin pump – because it is inactivated by gastrointestinal enzymes. There are three main types of insulin preparation: (a) short action (approximately six hours), with rapid onset; (b) intermediate action (approximately 12 hours); (c) long action, with slow onset and lasting for up to 36 hours. Human, porcine and bovine preparations are available. Much of the insulin now used is prepared by genetic engineering techniques from micro-organisms. There are many regimens of insulin treatment involving di?erent combinations of insulin; regimens vary depending on the requirements of the patients, most of whom administer the insulin themselves. Carbohydrate intake, energy expenditure and the presence of infection are important determinants of insulin requirements on a day-to-day basis.

A new treatment for diabetes, pioneered in Canada and entering its preliminary clinical trials in the UK, is the transplantation of islet cells of Langerhans from a healthy person into a patient with the disorder. If the transplantation is successful, the transplanted cells start producing insulin, thus reducing or eliminating the requirement for regular insulin injections. If successful the trials would be a signi?cant advance in the treatment of diabetes.

Scientists in Israel have developed a drug, Dia Pep 277, which stops the body’s immune system from destroying pancratic ? cells as happens in insulin-dependent diabetes. The drug, given by injection, o?ers the possibility of preventing type 1 diabetes in healthy people at genetic risk of developing the disorder, and of checking its progression in affected individuals whose ? cells are already perishing. Trials of the drug are in progress.... diabetes mellitus

Overactivity of the anterior lobe of the PITUITARY GLAND, causing ACROMEGALY (GIGANTISM).... hyperpituitarism

ACROMEGALY or gigantism is the result of the overactivity of, or tumour formation of cells in, the adenohypophysis which produces GROWTH HORMONE (see also PITUITARY GLAND). If this overactivity occurs after growth has ceased, acromegaly arises, in which there is gross overgrowth of the ears, nose, jaws, and hands and feet. DWARFISM may be due to lack of growth hormone.

DIABETES INSIPIDUS, a condition characterised by the passing of a large volume of URINE every day, is due to lack of the antidiuretic hormone (see VASOPRESSIN). Enhanced production of the ADRENOCORTICOTROPHIC HORMONE (ACTH) leads to CUSHING’S SYNDROME. Excessive production of PROLACTIN by micro or macro adenomas (benign tumours) leads to hyperprolactinaemia and consequent AMENORRHOEA and GALACTORRHOEA. Some adenomas do not produce any hormone but cause effects by damaging the pituitary cells and inhibiting their hormone production.

The most sensitive cells to extrinsic pressure are the gonadotrophin-producing cells and the growth-hormone producing cells, so that if the tumour occurs in childhood, growth hormone will be suppressed and growth will slow. Gonadotrophin hormone suppression will prevent the development of puberty and, if the tumour occurs after puberty, will result in amenorrhoea in the female and lack of LIBIDO in both sexes. The thyroid-stimulating hormone cells are the next to suffer and the pressure effects on these cells will result in hypothyroidism (see under THYROID GLAND, DISEASES OF).

Fortunately the ACTH-producing cells are the most resistant to extrinsic pressure and this is teleologically sound as ACTH is the one pituitary hormone that is essential to life. However, these cells can suffer damage from intracellular tumours, and adrenocortical insu?ciency is not uncommon.

Information about these disorders may be obtained from the Pituitary Foundation.... pituitary-linked disorders

Conditions of the tongue At rest, the TONGUE touches all the lower teeth and is slightly arched from side to side. It has a smooth surface with a groove in the middle and an even but de?nite edge. It is under voluntary control and the tip can be moved in all directions.

Ankyloglossia or tongue-tie is a rare disorder in which the frenum or band connecting the lower surface of the tongue to the ?oor of the mouth is so short or tight that the tongue cannot be protruded. Surgery can remedy the defect. It is easy to overdiagnose and is not a common cause of di?culty in feeding at birth or speech defects in infancy.

Gross enlargement of the tongue can make speech indistinct or make swallowing and even breathing di?cult. This is known as macroglossia and may be such that the tongue is constantly protruded from the mouth. The cause may be CONGENITAL, as in severe cases of DOWN’S (DOWN) SYNDROME, or it may occur as a result of ACROMEGALY or be due to abnormal deposits as in AMYLOIDOSIS.

A marked tremor of the tongue when protruded may be seen in various neurological diseases, but may be caused by alcoholism.

After a STROKE involving the motor nerve centre, the control of one side of the tongue musculature will be lost. This will result in the protruded tongue pointing to the side of the body which is paralysed. The sense of taste on one side of the tongue may also be lost in some diseases of the brain and facial nerve.

The presence of fur on the tongue may be obvious and distressing. This is due to thickening of the super?cial layers of the tongue which may appear like hairs which trap food debris and become discoloured. Furring is common during fever and as a result of mouth-breathing and smoking.

In some conditions the tongue may appear dry, red and raw (GLOSSITIS). An in?amed beefy tongue is characteristic of pellagra, a disease caused by de?ciency of NICOTINIC ACID in the diet. A magenta-coloured tongue may be seen when there is a lack of RIBOFLAVIN.

Ulcers of the tongue are similar to those elsewhere in the mouth. The most common are aphthous ulcers which are small, red and painful and last for about ten days. They are associated with stress, mild trauma (such as from jagged teeth), and occasionally with folic acid and vitamin B12 de?ciency. Ulcers of the tongue are sometimes found in patients with chronic bowel disease.... tongue, disorders of

A noncancerous tumour or cyst that resembles glandular tissue and arises from the epithelium (the layer of cells that lines the inside of

organs).

Adenomas of endocrine glands can cause excessive hormone production, leading to disease.

For example, pituitary gland adenomas can result in acromegaly or Cushing’s syndrome.... adenoma

Abnormal enlargement of the tongue.

Macroglossia is a feature of Down’s syndrome, hypothyroidism, and acromegaly.

It is also caused by some tumours of the tongue, such as a haemangioma or a lymphangioma.... macroglossia

Means high BLOOD PRESSURE (raised pressure of the circulating blood), but since there is a wide range of ‘normal’ blood pressure in the population, a precise level of pressure above which an individual is deemed hypertensive is arbitrary. (A healthy young adult would be expected to have a systolic pressure of around 120 mm Hg and a diastolic of 80 mm Hg, recorded as 120/80.) Hypertension is not a disease as such but a quantitative deviation from the norm. A person with a pressure higher than the average for his or her age group is usually symptomless – although sometimes such people may develop headaches. The identi?cation of people with hypertension is important because it is a signal that they will be more likely to have a STROKE or myocardial infarct (coronary thrombosis or heart attack) than someone whose pressure is in the ‘normal’ range. Preventive steps can then be taken to lessen the likelihood of their developing these potentially life-threatening conditions.

Blood pressure is measured using two values. The systolic pressure – the greater of the two – represents the pressure when blood is pumped from the left VENTRICLE of the heart into the AORTA. The diastolic pressure is the measurement when both ventricles relax between beats. The pressures are measured in millimetres (mm) of mercury (Hg). Despite the grey area between normal and raised blood pressure, the World Health Organisation (WHO) has de?ned hypertension as a blood pressure consistently greater than 160 mm Hg (systolic) and 95 mm Hg (diastolic). Young children have readings well below these, but blood pressure rises with age and a healthy person may well live symptom free with a systolic pressure above the WHO ?gure. A useful working de?nition of hypertension is the ?gure at which the bene?ts of treating the condition outweigh the risks and costs of the treatment.

Between 10 and 20 per cent of the adult population in the UK has hypertension, with more men than women affected. Incidence is highest in the middle-aged and elderly. Because most people with hypertension are symptomless, the condition is often ?rst identi?ed during a routine medical examination, otherwise a diagnosis is usually made when complications occur. Many people’s blood pressure rises when they are anxious or after exercise, so if someone’s pressure is above normal at the ?rst testing, it should be taken again after, say, 10 minutes’ rest, by which time the reading should have settled to the person’s regular level. BP measurements should then be taken on two subsequent occasions. If the pressure is still high, the cause needs to be determined: this is done using a combination of personal and family histories (hypertension can run in families), a physical examination and investigations, including an ECG and blood tests for renal disease.

Over 90 per cent of hypertensive people have no immediately identi?able cause for their condition. They are described as having essential hypertension. In those patients with an identi?able cause, the hypertension is described as secondary. Among the causes of secondary hypertension are:

Lifestyle factors such as smoking, alcohol, stress, excessive dietary salt and obesity.

Diseases of the KIDNEYS.

Pregnancy (ECLAMPSIA).

Various ENDOCRINE disorders – for example, PHAEOCHROMOCYTOMA, CUSHING’S DISEASE, ACROMEGALY, thyrotoxicosis (see under THYROID GLAND, DISEASES OF).

COARCTATION OF THE AORTA.

Drugs – for example, oestrogen-containing oral contraceptives (see under CONTRACEPTION), ANABOLIC STEROIDS, CORTICOSTEROIDS, NON-STEROIDAL ANTIINFLAMMATORY DRUGS (NSAIDS).

Treatment People with severe hypertension may need prompt admission to hospital for urgent investigation and treatment. Those with a mild to moderate rise in blood pressure for which no cause is identi?able should be advised to change their lifestyle: smokers should stop the habit, and those with high alcohol consumption should greatly reduce or stop their drinking. Obese people should reduce their food consumption, especially of animal fats, and take more exercise. Everyone with hypertension should follow a low-salt diet and take regular exercise. Patients should also be taught how to relax, which helps to reduce blood pressure and, if they have a stressful life, working patterns should be modi?ed if possible. If these lifestyle changes do not reduce a person’s blood pressure su?ciently, drugs to achieve this will be needed. A wide range of anti-hypertensive drugs are available on prescription.

A ?rst-line treatment is one of the THIAZIDES, e?ective at a low dosage and especially useful in the elderly. Beta blockers (see BETAADRENOCEPTOR-BLOCKING DRUGS), such as oxprenolol, acebutol or atenolol, are also ?rst-line treatments. ACE inhibitors (see ANGIOTENSIN-CONVERTING ENZYME (ACE) INHIBITORS) and CALCIUM-CHANNEL BLOCKERS can be used if the ?rst-line choices are not e?ective. The drug treatment of hypertension is complex, and sometimes various drugs or combinations of drugs have to be tried to ?nd what regimen is e?ective and suits the patient. Mild to moderate hypertension can usually be treated in general practice, but patients who do not respond or have complications will normally require specialist advice. Patients on anti-hypertensive treatments require regular monitoring, and, as treatment may be necessary for several years, particular attention should be paid to identifying sideeffects. Nevertheless, e?ective treatment of hypertension does enable affected individuals to live longer and more comfortable lives than would otherwise be the case. Older people with moderately raised blood pressure are often able to live with the condition, and treatment with anti-hypertensive drugs may produce symptoms of HYPOTENSION.

In summary, hypertension is a complex disorder, with di?erent patients responding di?erently to treatment. So the condition sometimes requires careful assessment before the most e?ective therapy for a particular individual is identi?ed, and continued monitoring of patients with the disorder is advisable.

Complications Untreated hypertension may eventually result in serious complications. People with high blood pressure have blood vessels with thickened, less ?exible walls, a narrowed LUMEN and convoluted shape. Sometimes arteries become rigid. ANEURYSM may develop and widespread ATHEROMA (fat deposits) is apparent in the arterial linings. Such changes adversely affect the blood supply to body tissues and organs and so damage their functioning. Patients suffer STROKE (haemorrhage from or thrombosis in the arteries of the BRAIN) and heart attacks (coronary thrombosis

– see HEART, DISEASES OF). Those with hypertension may suffer damage to the retina of the EYE and to the OPTIC DISC. Indeed, the diagnosis of hypertension is sometimes made during a routine eye test, when the doctor or optician notices changes in the retinal arteries or optic disc. Kidney function is often affected, with patients excreting protein and excessive salt in their urine. Occasionally someone with persistent hypertension may suffer an acceleration of damage to the blood vessels – a condition described as ‘malignant’ hypertension, and one requiring urgent hospital treatment.

Hypertension is a potentially dangerous disease because it develops into a cycle of self-perpetuating damage. Faulty blood vessels lead to high blood pressure which in turn aggravates the damage in the vessels and thus in the tissues and organs they supply with blood; this further raises the affected individual’s blood pressure and the pathological cycle continues.... hypertension

Any of the main arteries of the neck and head. There are 2 common carotid arteries (left and right), each of which divides into 2 main branches (internal and external).

The left carotid arises from the aorta and runs up the neck on the left side of the trachea (windpipe). The right carotid arises from the subclavian artery (which branches off the aorta) and follows a similar route on the right side of the

neck. Just above the level of the larynx (voice-box), each carotid artery divides to form an external carotid artery and an internal carotid artery. The external arteries have multiple branches that supply most tissues in the face, scalp, mouth, and jaws; the internal arteries enter the skull to supply the brain and eyes. At the base of the brain, branches of the 2 internal carotids and the basilar artery join to form a ring of vessels called the circle of Willis. Narrowing of these vessels may be associated with transient ischaemic attack (TIA); obstruction of them causes a stroke. carpal tunnel syndrome Numbness, tingling, and pain in the thumb, index finger, and middle fingers caused by compression of the median nerve at the wrist. Symptoms may be worse at night. The condition results from pressure on the nerve where it passes into the hand via a gap (the “carpal tunnel’’) under a ligament at the front of the wrist. It is common among keyboard users. It also occurs without obvious cause in middleaged women, and is associated with pregnancy, initial use of oral contraceptives, premenstrual syndrome, rheumatoid arthritis, myxoedema, and acromegaly.

The condition often disappears without treatment.

Persistent symptoms may be treated with a corticosteroid drug injected under the ligament, or the ligament may be cut to relieve pressure on the nerve.... carotid artery

A suffix meaning enlargement, as in acromegaly, a condition in which there is enlargement of the skull, jaw, hands, and feet due to excess production of growth hormone.... megaly

A somatostatin analogue, a hormone that acts on the pituitary gland.

Given by injection, octreotide is used mainly in the treatment of acromegaly and hormone-secreting intestinal tumours.

Octreotide is also used to prevent complications following pancreatic surgery.

Side effects may include various gastrointestinal disturbances such as nausea, vomiting, abdominal pain and bloating, flatulence, and diarrhoea.... octreotide

Growths in the pituitary gland. Pituitary tumours are rare, and mostly noncancerous, but tumour enlargement can put pressure on the optic nerves, causing visual defects.

The causes of pituitary tumours are unknown. They may lead to inadequate hormone production, causing problems such as cessation of menstrual periods or reduced sperm production. They may also cause the gland to produce excess hormone. Overproduction of growth hormone causes gigantism or acromegaly; too much thyroid-stimulating hormone (TSH) can lead to hyperthyroidism. Investigations include blood tests, X-rays, MRI of the pituitary, and usually also vision tests. Treatment may be by surgical removal of the tumour, radiotherapy, hormone replacement, or a combination of these techniques. The drug bromocriptine may be used; it can reduce production of certain hormones and shrink some tumours.... pituitary tumours

Synthetic versions of the hormone somatostatin that acts on the pituitary gland, controlling the release of growth hormone.

These drugs are used to treat acromegaly and symptoms associated with some other hormone-secreting tumours (particularly in carcinoid syndrome).

Octreotide is a common somatostatin analogue.... somatostatin analogues

n. abnormal enlargement of the fingers and toes, occurring either as a congenital abnormality or as part of an acquired disease (such as *acromegaly).... pachydactyly

(growth-hormone-release inhibiting hormone) a hormone produced by the hypothalamus and some extraneural tissues, including the gastrointestinal tract and pancreas (see islets of Langerhans), that acts to inhibit the secretion of many hormones. For example, in the pituitary gland it inhibits the release of *growth hormone (somatotrophin) and in the pancreas it suppresses secretion of insulin and glucagon. Somatostatin analogues are used to treat *acromegaly (caused by overproduction of growth hormone) and to relieve the symptoms caused by hormone-secreting neuroendocrine tumours, including *carcinoid tumours. They include lanreotide (also licensed for the treatment of thyroid tumours) and octreotide (also used to reduce vomiting in palliative care and to treat *oesophageal varices); gastrointestinal upsets (e.g. nausea, loss of appetite, abdominal pain, diarrhoea) are the most common side-effects.... somatostatin