Hepatitis A, B, C, D, and E. Update on testing and treatment.

Five major types of viral hepatitis have been identified. Hepatitis A is an acute, usually self-limited illness. Prophylaxis with immune globulin (Gamastan, Gammar) is effective in household and sexual contacts of infected patients. Hepatitis B has both acute and chronic forms. Treatment trials for chronic hepatitis B with interferon alfa-2b have shown promise. Hepatitis C is the name now given to non-A non-B hepatitis. Interferon alfa-2b (Intron A) has been approved for treatment of chronic hepatitis C. Hepatitis D occurs only in patients with hepatitis B. The only treatment for hepatitis D is prevention of hepatitis B. Hepatitis E is seen after natural disasters in developing regions of the world. Further advances in serologic testing and treatment of viral hepatitis can be expected.