Poynard T. Treatment of chronic hepatitis B virus infection in patients co-infected with human immunodeficiency virus

Chronic infection with hepatitis B virus (HBV) affects about 5 % of the world population (1). In Western Europe, Australia and the USA prevalence of chronic carriers of hepatitis B surface antigen (HBsAg) is less than 1 % of the population. Among human immunodeficiency virus (HIV) infected individuals this prevalence is approximately 10 fold higher (2). Until recently, studies on HBV infection in HIV seropositive patients have not been emphasized. The natural history of chronic HBV infection is modified by co-infection with HIV. After initial HBV infection, both development and persistence of chronic HBV infection are greater in patients with prior HIV infection (3, 4). Among chronic hepatitis B surface antigen (HBsAg) carriers a high level of HBV replication or the presence of hepatitis B e antigen (HBeAg) are common in HIV/HBV co-infected individuals (3, 4). These 2 conditions may be predictive of poor survival. However, studies performed prior to the era of highly active antiretroviral therapy (HAART) (prior to 1997), found mild necroinflammatory liver lesions associated with low serum transaminases in deeply immunossupressed HIV/HBV co-infected patients (5-8). More recent studies, conducted in HAART era, have reported a higher incidence rate of liver related cirrhosis and mortality in HIV/HBV co-infected patients compared to HIV mono-infected persons (9, 10). Factors impacting progression to cirrhosis in HIV/HBV co-infected patients remain unknown. HAART-related immune restoration may have switched the immune reaction to HBV from a tolerance to an intolerance phase, leadin