[Clinical aspects and therapy of toxic hepatitis]

The different types of hepatotoxicity can be induced by drugs. Approximately 2%-5% of patients require hospitalization for jaundice. Drug-induced hepatic lesions are responsible for 10% of hepatitis cases in adults. Most hepatotoxic drug reactions are idiosyncratic and classified either as immunologic (hipersensitivity) or metabolic. In contrast to intrinsic hepatotoxins, these reactions are not dose-dependent nor predictable. The enzyme system responsible for drug biotransformation in liver is cytochrome P450, a large multigene family of enzymes with 300 members. Clinical presentation in patients who develop drug hepatotoxicity can be asymptomatic with mild biochemical abnormalities, resembling acute hepatitis or chronic autoimmune hepatitis, veno-occlusive disease and cirrhosis. Withdrawal of the drug usually leads to reversal of the lesion. A spectrum of drug induced hepatotoxicity, diagnosis and treatment is reviewed.