With improved survival following the introduction of highly active antiretroviral therapy (HAART), liver disease has become a leading cause of death among HIV-infected persons in Western cohorts, primarily affecting those co-infected with hepatitis B or C viruses (HBV, HCV). However, data are sparse on liver disease in HIV-infected populations from Uganda and other African nations, where the etiologies of liver disease are broader and include aflatoxin, schistosomiasis and other infectious and environmental agents. Our previous noninvasive study in rural, Rakai, Uganda indicates that the prevalence of significant liver fibrosis is high among HIV-infected individuals (17%) and is 50% higher than in HIV-uninfected persons, although the prevalence of viral hepatitis B co-infection is low (5%). The study presented here is a biopsy-based study that follows up on these results with the objectives of defining the etiology of liver disease and describing the mechanisms of HIV-accelerated liver fibrosis in this setting.