Chronic fatty diarrhoea

Causes of steatorrhoea include abnormalities of the small intestine and insufficiency of the exocrine pancreas. Calcification of the pancreas in chronic pancreatitis can be seen in 50% of cases (X-ray of the abdomen). Concomitant diabetes mellitus should be searched for. Non-infectious causes of intestinal abnormalities such as coeliac disease (hypersensitivity to gluten) and intestinal lymphoma are rare. Coeliac disease is associated with antibodies against gliadin (a component of gluten) and autoantibodies against tissue transglutaminase (anti-endomysium antibodies). People with this disorder are often HLA-DQ2-positive.

Some infections may result in malabsorption:

• Giardia lamblia: microscopy of the faeces. These are often asymptomatic infections, so their importance should not be overestimated. Giardia can also give rise to secondary lactose-malabsorption: dairy products can no longer be tolerated.

• Capillaria philippinensis: occurs mainly in the Far East but is rare. Infection is caused by eating raw fresh water fish. Like Strongyloides, this worm also leads to endogenous reinfection. It can therefore reproduce in the body, unlike most other worms. The eggs and larvae can be found in the stools (repeated analyses are necessary). Treatment is with mebendazole (Vermox®). It is a potentially fatal infection.

• Strongyloides stercoralis: Serious infections cause diarrhoea, eosinophilia, pruritus and larva currens. The stools contain seldom eggs but larvae are present.

• Cryptosporidia can cause malabsorption. The possibility of AIDS must be excluded. The parasite can be demonstrated using Ziehl stain.

• Cyclospora can be compared with "large cryptosporidia" with variable acid-fastness on Ziehl stain. Treatment with cotrimoxazole is effective.

• Tropical sprue is a disease of unknown origin, common in Asia but less so in Africa. The disease responds to treatment with tetracyclines and folic acid.

Category: Medical Subject Notes , Medicine Notes