Daño hepático inducido por drogas

RESUMO

Drug induced liver disease is responsible of 5 percent of hospital admissions for jaundice in USA, and 10 percent of acute hepatitis in France and North Europe. In addition, 20 to 50 percent of the cases of fulminant hepatic failure in USA are due to drugs. Tradicionally drug induced liver disease has been divided in two groups : 1. Non predictable toxicity (idiosyncratic reaction). 2. Predictable toxicity (Intrinsec toxicity). From the clinical point of view, most of the patients present jaundice associated with elevation of aminotransferases and alkaline phosphatase. However, some patients presents acute liver failure and death. Te duration of illness permit another classification in two groups : acute, frequently characterized by microvesicular steatosis; a picture similar to acute viral hepatitis or biliary obstruction (cholestasic jaundice) with elevated alkaline phosphatase and pruritus. Chronic, manifested by different presentations such as acute hepatitis, chronic hepatitis, (autoimmune), sclerosing cholangitis, phospholipidosis and non cirrhotic or cirrhotic portal hypertension. Histologically drug toxicity can induce the following morphologic changes : a) Pure cholestasis more frequently seen with estrogens. b) Viral hepatitis like. c) Fulminant hepatic failure more commonly seen with halotane, acetaminophen, phenytoin and methyldopa shows multilobular necrosis frequently asssociated with hypersensitivity features (fever, pruritus, eosinofilia)...