Hepato-pancreato-biliary fat: the good, the bad and the ugly.

Obesity has become epidemic in the United States, in Europe, and in many urban areas in the developing world. The globalization of certain 'fast foods' and 'soft drinks' may, in part, be contributing to this epidemic. Diets high in saturated fatty acids and trans fats as well as drinks that have high fructose corn syrup levels may be particularly harmful. Recent research suggests that fat is a dynamic endocrine organ and that visceral fat is associated with the metabolic syndrome. Central obesity leads to organ steatosis and altered serum adipokines including reduced adiponectin and markedly elevated leptin. This abnormal adipokine milieu results in increased tissue infiltration of monocytes and macrophages which produce proinflammatory cytokines that alter organ function. Over many years, the combination of steatosis and local inflammation leads to fibrosis and eventually to cancer. Nonalcoholic fatty liver disease (NAFLD) is a precursor for nonalcoholic steatohepatitis (NASH). NAFLD and NASH (1) lead to cirrhosis and hepatocellular carcinoma, (2) increase the risk of liver resection, and (3) compromise the outcome of liver transplantation. Similarly, in the pancreas nonalcoholic fatty pancreas disease (NAFPD) may lead to nonalcoholic steatopancreatitis (NASP). NAFPD and NASP may (1) promote the development of chronic pancreatitis and pancreatic cancer, (2) exacerbate the severity of acute pancreatitis, and (3) increase the risk of pancreatic surgery. In the gallbladder nonalcoholic fatty gallbladder disease (NAFGBD, cholecystosteatosis) may lead to steatocholecystitis. Cholecystosteatosis may be an explanation for (1) the increased incidence of chronic acalculous cholecystitis and (2) the increased number of cholecystectomies.