Hepatitis A and B superimposed on chronic liver disease: vaccine-preventable diseases.

A number of studies have demonstrated that the acquisition of hepatitis A or hepatitis B in patients with chronic liver disease is associated with high rates of morbidity and mortality. Superimposition of acute hepatitis A in patients with chronic hepatitis C has been associated with a particularly high mortality rate, and chronic hepatitis B virus coinfection with hepatitis C virus is associated with an accelerated progression of chronic liver disease to cirrhosis, decompensated liver disease and hepatocellular carcinoma. With the availability of vaccines against hepatitis B and hepatitis A since 1981 and 1995, respectively, these are vaccine-preventable diseases. Studies have confirmed that hepatitis A and hepatitis B vaccines are safe and immunogenic in patients with mild to moderate chronic liver disease. However, hepatitis A and B vaccination is less effective in patients with advanced liver disease and after liver transplantation. These observations have led to the recommendation that patients undergo hepatitis A and B vaccination early in the natural history of their chronic liver disease. Vaccination rates are low in clinical practice, and public health and educational programs are needed to overcome barriers to facilitate timely implementation of these recommendations.