Depur-ttnent o/ Patho1og.v. Uniuersctv o j Toronto. Toronto, Canada, M5G 2C4 Steatohepatitis (fatty liver hepatitis), histologically identical to alcoholic disease, occurs in some obese patients after jejunoileal bypass. A similar lesion occurs rarely in obese patients without bypass surgery, but the risk factors are poorly understood. Hepatic steatosis, steatohepatitis and fibrosis were sought in 351 apparently nonalcoholic patients at autopsy and various risk factors were evaluated. Incidence of steatosis and steatohepatitis correlated with the degree of obesity. Steatohepatitis was found in 18.5% of markedly obese patients and 2.7% of lean patients. Additional risk factors for steatohepatitis were type I1 diabetes, weight loss in the preterminal period shortly before death and intravenous glucose therapy in the last week of life. Severe fibrosis was found in 13.8% of markedly obese patients and in 6.6% of lean patients; this difference was largely explained by the higher prevalence of diabetes in obese groups.
The risk factors defined in this study are known to be associated with abnormalities of free fatty acid metabolism. Obesity, type I1 diabetes and intravenous glucose therapy are associated with hyperinsulinemia, which may inhibit fatty acid oxidation. Obesity and weight loss increase the presentation of fatty acids to the liver. Similar metabolic changes may occur in obese patients after jejunoileal bypass surgery. Thus this study supports the hypothesis that fatty acids have a role in the hepatocellular necrosis found in some obese individuals. (HEPATOLOGY 1990;12: 1106-1 110.)
It is well known that large-droplet fatty change isteatosis) of the liver is common in asymptomatic obese individuals. Recently it has become evident that some obese nonalcoholic individuals, especially women, have steatosis accompanied by significant hepatic necrosis with Mallory bodies (steatonecrosis or steatohepatitis ) and progression to cirrhosis i 1-6 I Although it is known that this progressive disease is especially likely to develop in morbidly obese patients undergoing jejunoileal bypass surgery (7-101, the risk of significant obesity-