AIDS AND THE GUT

There are increasing challenges for the practising gastroenterologist in treating AIDS-related gastrointestinal diseases. The differential d iagnoses of dysphagia and odynophagia include cytomegalovirus (CMV) an d herpes simplex virus (HSV) infection, non-specific aphthous ulcerati on and non-AIDS oesophageal diseases, especially reflux oesophagitis. Chronic subacute abdominal pain with nausea, vomiting, early satiety a nd weight loss is suggestive of an obstructive lesion caused by lympho ma or Kaposi's sarcoma. Severe acute abdominal pain can indicate pancr eatitis or intestinal perforation due to cytomegalovirus. Right upper quadrant pain (with or without fever, vomiting or abnormal liver funct ion tests with a cholestatic profile) is suggestive of hepatobiliary p athology including cholecystitis, cholangitis, acalculous cholestatic and AIDS cholangiopathy. Diarrhoea is the most common gastrointestinal symptom of AIDS, affecting 50-90% of patients. Causes of AIDS diarrho ea include protozoa (Cryptosporidium parvum, Isospora belli, Enterocyt ozoon bieneusi, Septata intestinalis, Cyclospora spp, Entamoeba histol ytica and Giardia lamblia), bacteria (Mycobacterium avium-intracellula re, Clostridium difficile, Salmonella, Shigella and Campylobacter jeju ni), and viruses (CMV, HSV and possibly HIV). Chronic diarrhoea, malnu trition and weight loss can shorten the life-span of patients with AID S. Elemental diets, isotonic formulas, medium chain triglycerides and total parenteral nutrition have been tried with little success in AIDS patients with severe diarrhoea and wasting.