WOTD: Onychogryphosis

The effects of onychogryphosis. Photograph: Elord @wikidoc.org

"Onychogryphosis" - Abnormal thickening, hardening, and curving of the nails that occurs mainly in elderly people. Onychogryphosis may be associated with fungal infection or poor circulation.

"onychogryphosis". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p414.

WOTD: Prolactinoma

Side-view MRI scan showing a Prolactinoma. Photograph: UCLA Neurosurgery

"Prolactinoma" - A noncancerous tumour of the pituitary gland the causes over-production of prolactin. In women, this may result in galactorrhoea, amenorrhoea, or infertility. In men, it may cause erectile dysfunction and gynaecomastia. In either sex, it may cause headaches, diabetes insipidus, and, if the tumour presses on the optic nerves, loss of the outer visual field. Diagnosis is made from blood tests and CT scanning or MRI of the brain. Treatment may involve removal of the tumour, radiotherapy or giving the drug bromocriptine.

"prolactinoma". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p466.

WOTD: Embolism

A CT scan showing a pulmonary embolism. Photograph: mediexchange.com

"Embolism" - Blockage of an atery by an embolus. Blood clots that have broken off from a larger clot located elsewhere in the circulation are the most common type of embolus. Pulmonary embolism is usually the result of a fragment breaking off from a deep vein thrombosis and being carried via the heart to block an artery supplying the lungs; this is a common cause of sudden death. Blood clots may form on the heart lining after a myocardial infarction, or in the atria in atrial fibrillation, and then travel to the brain, resulting in a cerebral embolism, which is an important cause of stroke.

Symptoms of an embolism depend on the site of the embolus. Pulmonary embolism can lead to breathlessness and chest pains. If the embolus lodges in the brain, a stroke may occur, affecting speech, vision, or movement. If an embolism blocks an artery to the leg, the limb will become painful and turn white and blue. Untreated, gangrene may develop. In serious cases of fat embolism, heart and breathing rates rise dramatically, and there is restlessness, confusion, and drowsiness.

Embolectomy (surgery to remove the blockage) may be possible. If surgery is not possible, thrombolytic and anticoagulant drugs may be given.

"embolism". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p196.

WOTD: Venepuncture

A contrast-enhanced venography in a 78 year-old man with thrombosis of the deep veins in the lower leg.

Photograph: ajronline.org

"Venography" - A diagnostic procedure that enables veins to be seen on an X-ray film after they have been injected with a substance opaque to X-rays. It is used to detect abnormalities or diseases of the veins, such as narrowing or blockage from thrombosis.

"venography". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p581.

WOTD: Barotrauma

Chest x-ray of Barotrauma in a patient with status asthmaticus. Photograph: realicu.com

"Barotrauma" - Damage or pain, mainly affecting the middle ear and facial sinuses, that is caused by changes in surrounding air pressure. Air travellers are at the greatest risk, but scuba divers face similar problems.

Aircraft cabin pressure decreases as the plane ascends and increases as it descends. As the aircraft ascends, the ears may "pop" as the air in the middle ear expands and is expelled via the eustachian tubes, which connect the middle ear to the back of the throat. On descent, the higher pressure may push the eardrum inwards and cause pain. Minor pressure damage in the middle ear may cause pain, hearing loss, and tinnitus for a few days; damage within the facial sinuses may also cause pain, and possibly a discharge of mucus or blood. Symptoms usually wear off within hours or days, but treatment may be needed if they worsen or persist. Large pressure changes can rupture the eardrum.

Barotrauma can be avoided by vigorous swallowing or by forcibly breathing out with the mouth closed, and the nose pinched (the Valsalva manoeuvre). This action equalises the internal and external pressures in the middle ear and sinuses. If the eustachian tubes are blocked, as commonly occurs with a cold, use of a nasal spray containing a decongestant drug is recommended shortly before the descent of the aircraft. 

"barotrauma". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p66.

WOTD: Talipes

Left congenital talipes as seen by three-dimensional ultrasound at 22 weeks gestation. 
Photograph: International Federation of Gynecology and Obstetrics

"Talipes" - A birth defect (commonly called club-foot) in which the foot is twisted out of shape or position. The cause may be pressure on the feet from the mother's uterus, or a genetic factor. The most common form is an equinovarus deformity, in which the heel turns inwards and the rest of the foot bends down and inwards. It is treated by repeated manipulation of the foot and ankle, starting soon after birth. A plaster cast, or strapping may be used to hold the foot in position. If this is not successful, surgery will be needed.

"talipes". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p538.

WOTD: Retinoblastoma

A young child with retinoblastoma in the left eye. Photograph: Gordon K. Klintworth

"Retinoblastoma" - A cancer of the retina that affects infants. The first indications of this disorder may be a squint caused by blindness in the affected eye or a visible whiteness in the pupil. Without early treatment, retinoblastoma can spread to the orbit (eye socket) and along the optic nerve to the brain.

Retinoblastoma has a genetic basis. People with this cancer lack part of one of the chromosomes in pair number 13. Newborn infants from affected families should have genetic counselling.

Treatment is by removing the eye, or by radiotherapy. If both eyes are involved, the one worse affected by removed and the other given radiotherapy.

"retinoblastoma". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p489.

WOTD: Phaeochromocytoma

Phaeochromocytoma on an MRI scan. Photograph: endocrinediseases.org

"Phaeochromocytoma" - A rare tumour of cells that secrete epinephrene (adrenaline) and norepinephrine (noradrenaline). It causes increased production of these hormones, leading to hypertension. The tumours usually develop in the medulla (core) of the adrenal glands, and are most common in young to middle-aged adults.

Hypertension is the only sign most of the time, but pressure on the tumour, emotional upset, change in posture, or taking beta-blocker drugs can cause a surge of hormones. This surge brings on a sudden rise in blood pressure, palpitations, headache, nausea, vomiting, facial, flushing, sweating, and, sometimes, a feeling of impending death.

Blood tests and urinalysis are used to make a diagnosis, CT scanning, MRI, and radioisotope scanning may be used to locate the tumours, which are then usually removed surgically. Follow-up medical checks are required because the condition occasionally recurs.

"phaeochromocytoma". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p445.

WOTD: Scoliosis

A scoliosis x-ray. Photograph: thefamilychiro.com.au

"Scoliosis" - A deformity in which the spine is bent to one side. The thoracic or lumbar regions are most commonly affected. Scoliosis usually starts in childhood or adolescence and becomes progressively more marked until growth stops. In many cases, another part of the spine curves to compensate, resulting in an S-shaped spine. The cause of juvenile scoliosis is unknown. Rarely, scoliosis is due to a congenital abnormality of the vertebrae.

In some cases, physiotherapy may be sufficient to control scoliosis. Progressive or severe scoliosis may require immobilisation of the spine in a brace, followed by surgery (spinal fusion) to straighten it.

"scoliosis". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p500-501.

WOTD: Bronchiectasis

A chest x-ray of a patient suffering cystic fibrosis with bronchiectasis. Photograh: learningradiology.com

"Bronchiectasis" - A lung disorder in which one or more bronchi (the air passages leading from the trachea) are abnormally widened, distorted, and have damaged linings. Bronchiectasis most often develops during childhood and was once commonly associated with infections such as measles and pertussis (whooping cough). The condition is also a complication of cystic fibrosis. It results in pockets of long-term infection which the airways and the continuous production of large volumes of green or yellow sputum (phlegm), Extensive bronchiectasis causes shortness of breath. The symptoms are usually controlled with antibiotic drugs and postural drainage. If the condition is confined to one area of the lung, surgical removal of the damaged area may be recommended. 

"bronchiectasis". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p98.

WOTD: Spondylolysis

A sagittal x-ray of a female patient with L4 spondylolysis. Photograph: Spineuniverse.com

"Spondylolysis" - A disorder of the spine in which the arch of the 5th (or, rarely, the 4th) lumbar vertebra consists of soft fibrous tissue instead of normal bone. As a result, the arch is weak and prone to damage, which may produce spondylolisthesis (the slipping forward of a vertebra over the one below it.) Otherwise, spondylolysis is usually symptomless.

"spondylolysis". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p522.

WOTD: Osteochondroma

An osteochondroma on the fibula. Photograph: tumorlibrary.com

"Osteochondroma" - A noncancerous bone tumour, which is formed from a stalk of bone capped with cartilage, and appears as a hard round swelling near a joint. An osteochondroma develops in late childhood and early adolescence, usually from the side of a long bone near the knee or shoulder. The tumour causes problems only if it interferes with movement of tendons or the surrounding joint, in which case it may be removed surgically. Large osteochondromas can interfere with skeletal growth, causing deformity.

"osteochondroma". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p422.

WOTD: Astrocytoma

An MRI scan showing an astrocytoma. Photograph: Mayfield Clinic

"Astrocytoma" - A type of cancerous brain tumour. Astrocytomas are the most common type of glioma, a tumour arising from glial (supporting) cells in the nervous system. They most commonly develop in the cerebrum (the main mass of the brain). Astrocytomas are classified in four grades (I-IV) according to their rate of growth and malignancy. The most severe and common type is called glioblastoma multiforme. Symptoms are similar to those of other types of brain tumour. Diagnostic tests include CT scanning or MRI. Treatment is with surgery and, in some cases, radiotherapy and/or chemotherapy.

"astrocytoma". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p56.

WOTD: Vasculitis

Cutaneous Vasculitis. Photograph: aic.cuhk.edu.hk

"Vasculitis" - Inflammation of blood vessels. Vasculitis usually leads to damage to the lining of vessels, with narrowing or blockage, that restricts or stops blood flow. As a result, the body tissues supplied by the affected vessels are damaged or destroyed by ischaemia.

Vasculitis is thought to be caused in most cases by the presence of minute bodies, called immune complexes (consisting of antigens bound to antibodies) are normally destroyed by white blood cells, but sometimes adhere to the walls of blood vessels, where they cause inflammation. In some cases, the antigens are viruses. Vasculitis is the basic disease process in a number of disorders, including  polyarteritis nodosa, erythema nodosum, Henoch-Schönlein purpura, serum sickness, temporal arteritis, and Buerger's disease.

"vasculitis". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p578.

WOTD: Periodontitis

A 60 year old patient with severe chronic periodontitis. Photograph: Augustin Zeron

"Periodontitis" - Inflammation of the periodontium (the tissues surrounding the teeth.) There are two types: periapical and chronic. Periapical periodontitis results from neglected dental caries and occurs when bacteria enter the tooth pulp and spread to the root tip, sometimes causing a dental abscess, granuloma, or cyst. Chronic periodontitis is a result of untreated gingivitis, in which bacteria attack the periodontal tissues. This type is the major cause of adult tooth loss.

Periapical periodontitis may cause toothache, especially on biting. An abscess may make the tooth loss; a large dental cyst may cause swelling of the jaw. In chronic periodontitis, the signs of gingivitis are present.

Periodontitis is diagnosed by a dental examination and dental x-rays. Periapical periodontitis is treated by draining pus and filling the tooth or by extraction. 

Regular teeth cleaning can prevent advanced chronic periodontal disease and further destruction of the tissues. Treatment may include root planing, scaling, gingivectomy, or curettage. Sometimes, loose teeth can be anchored to firmer teeth by splinting.

"periodontitis". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p441.

WOTD: Osteomalacia

X-ray appearances of the wrist and knee in osteomalacia (A) before treatment (B) after six months of treatment

Photograph: BMJ

"Osteomalacia" - Softening, weakening, and demineralisation of bones in adults due to vitamin D deficiency. Osteomalacia is rare in developed countries. It is most commonly affects housebound, elderly, and dark-skinned people live in countries that have less sunlight than their country of origin.

Healthy bone production requires calcium and phosphorus, which cannot be absorbed from the diet without sufficient vitamin D. Causes of osteomalacia include a diet low in vitamin D; malabsorption in conditions like coeliac disease or after intestinal surgery; or insufficient exposure to sunlight.

Osteomalacia causes bone pain, muscle weakness, and, if the blood level of calcium is very low, tetany. Weakened ones are vulnerable to distortion and fractures. Treatment is with a diet rich in vitamin D and increased exposure to sunlight; vitamin D supplements may also be given if osteomalacia is due to malabsorption.

"osteomalacia". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p423.

WOTD: Myxoma

An x-ray of an atrial myxoma. Photograph: radiopaedia.com

"Myxoma" - A noncancerous, jelly-like tumour composed of soft mucous material and loose fibrous strands. Myxomas usually occur singly, and may sometimes grow very large. They may develop under the skin, in the abdomen, in the bones or, very rarely, inside the cavities of the heart. In this case, thrombi (blood clots) may form, and the flow of blood through the heart may be obstructed. Myxomas can usually be successfully removed by surgery.

"myxoma". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p387.

WOTD: Encephalopathy

A CT scan of an 11 year old child with progressive encephalopathy secondary to HIV.
Photograph: rihes.cmu.ac.th

"Encephalopathy" - Any disorder affecting the brain, especially chronic degenerative conditions.

Wernicke's encephalopathy is a degenerative condition of the brain caused by deficiency of Vitamin B1. It's most common in those with chronic alcohol dependence. Hepatic encephalopathy is caused by the effect on the brain of toxic substances that have built up in the blood as a result of liver failure. It may lead to impaired consciousness, memory loss, a change in personality tremors and seizures.

Bovine spongiform encephalopathy, or BSE, is a disorder contracted by cattle after they are given feed containing material from other cattle or sheep. 

Other causes of encephalopathy include HIV infection, chickenpox, and Reye's syndrome. Treatment of encephalopathy depends on the cause.

"encephalopathy". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p199.

WOTD: Neurosyphilis

An MRI scan showing neurosyphilis. Photograph:  Dr Roberto Schubert

"Neurosyphilis" - Infection of the brain or spinal cord that occurs in untreated syphilis many years after initial infection.

Damage to the spinal cord due to neurosyphilis may cause tabes dorsalis, characterised by poor co-ordination of leg movements, urinary incontinence, and pains in the abdomen and limbs. Damage to the brain may cause dementia, muscle weakness, and, in rare cases, total paralysis of the limbs.

"neurosyphilis". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p400.

WOTD: Osteoporosis

The neck of the right femur is fractured due to osteoporosis. Photograph: medlib.med.utah.edu

"Osteoporosis" - An inherited disorder in which bones harden and become denser. Deficiency of one of the two types of bone cell responsible for healthy bone growth results in a disruption of normal bone structure. In its mildest form, there may be no symptoms, more severe forms of osteoporosis result in abnormally high susceptibility to fractures, stunted growth; deformity; and anaemia. Pressure on nerves may cause blindness, deafness, and facial paralysis.

Most treatments for osteoporosis aim to reduce the severity of symptoms. Bone marrow transplants of cells from which healthy bone cells might develop are undertaken in some cases.

"osteoporosis". British Medical Association (2007). Illustrated Medical Dictionary. 2nd ed. London: Dorling Kindersley (DK). p423-424.