hepatic and biliary disorders
Hepatitis D
Introduction
Hepatitis D is caused by a defective RNA virus (delta agent) that can replicate only in the presence of hepatitis B virus. It occurs uncommonly as a coinfection with acute hepatitis B or as a superinfection in chronic hepatitis B. (See also Causes of Hepatitis , Hepatitis D is usually transmitted by parenteral or mucosal contact with infected blood or body fluids. Infected hepatocytes contain delta particles coated with hepatitis B surface antigen (HBsAg). Prevalence of hepatitis D virus (HDV) varies widely geographically, with endemic pockets in several countries. Parenteral drug users are at relatively high risk, but HDV, unlike hepatitis B virus (HBV), has not widely permeated the MSM (men-who-have-sex-with-men) community. 