Epidemiology of HBV infection in a cohort of Ugandan HIV-infected patients and rate and pattern of lamivudine-resistant HBV infection in patients receiving antiretroviral therapy.

BACKGROUND Many HIV-infected patients in sub-Saharan Africa are not routinely screened for hepatitis B virus (HBV) infection and are on antiretroviral therapy (ART) regimens containing only lamivudine as anti-HBV active drug. METHODS In 2009-2011, we screened for hepatitis B surface antigen (HBsAg) in 2820 HIV-infected adults patients at the Mbarara Hospital Uganda and investigated risk factors for HBV infection. Using samples of dried plasma or blood spots, we tested for HBV viral load and HBV drug resistance mutations in all HBsAg-positive patients on ART for ≥ 12 months. RESULTS In this study, 109 patients tested HBsAg positive (3.9%; 109/2820). HBsAg-positive patients were more likely to have had >4 lifetime sexual partners (p<0.01). Of the 55 HBsAg-positive patients on ART for ≥ 12 months, 53 were only on lamivudine as anti-HBV active drug and two were on tenofovir and lamivudine. HBV-DNA was detected in 30 patients (54.5%; 30/55), all on lamivudine-monotherapy. Of the 23 patients in whom HBV-DNA sequencing was successful, 17 had lamivudine-resistant HBV strains harbouring rtM204V/I mutations accompanied by secondary/compensatory mutations. CONCLUSIONS Our study suggests that sexual transmission may represent a major mode of spread of HBV in southwest Uganda and confirms the importance of screening for HBV and of using ART regimens containing tenofovir in HIV/HBV co-infected patients.