Analysis of occult hepatitis B virus infection in liver tissue of HIV patients with chronic hepatitis C.

OBJECTIVE Current data on the prevalence of occult hepatitis B virus (HBV) infection in HIV-positive individuals conflict. As occult HBV infection could have an impact on the outcome of liver disease in HIV-positive patients, we investigated a large number of HIV-positive/HBV-surface-antigen (HBsAg) negative subjects with hepatitis C virus (HCV) infection by using the 'gold standard' approach for occult HBV detection--analysis of liver DNA extracts. METHODS The presence or absence of HBV DNA was determined by PCR testing of four different viral genomic regions in DNA extracts of needle liver biopsy specimens of 101 HBsAg negative individuals with HIV/HCV co-infection. HBV genotyping was performed by sequencing analysis of the preS-S gene in occult HBV isolates from 18 cases. RESULTS Occult HBV infection was diagnosed in 42 of the 101 cases (41%). No clinically relevant difference was found between occult HBV-positive and -negative patients. HBV genotype D and A were detected, respectively, in 11 (61%) and 7 (39%) of 18 cases analysed. CONCLUSIONS Occult HBV infection frequently occurs in HIV/HCV co-infected patients indicating the importance of performing prospective studies able to clarify its clinical impact in these patients. HBV genotype A is highly prevalent in HIV-infected subjects with occult HBV infection in a similar way to HBsAg/HIV-positive individuals.