Serum triglycerides, the liver and the pancreas.

Massive hypertriglyceridaemia associated with fatty liver and abdominal pain or frank pancreatitis (the chylomicronaemia syndrome) is uncommon, but clinically important and under-recognized. It may arise as a result of severe genetic defects in lipolysis or, more commonly, from a moderate primary hypertriglyceridaemia that is exacerbated by a secondary cause. The latter include several drugs, among which the protease inhibitors, used for the treatment of human immunodeficiency virus infection, are increasingly apparent. In the acute situation plasma exchange, fat-free parenteral nutrition and acute insulin treatment, even in nondiabetic persons, may be valuable. A potentially major advance in prophylaxis is the use of high-dose antioxidant therapy, which has been shown to reduce attacks of pancreatitis even in the absence of a reduction in serum triglycerides. Asymptomatic patients with abnormal liver function tests are common in the lipid clinic, and can be a difficult group in which to make management decisions. Among those who are not taking excessive amounts of alcohol, many will have nonalcoholic steatohepatitis. The care of these patients is discussed, but there remains considerable uncertainty regarding their optimum management and prognosis.