['There are conflicting data regarding the incidence and factors implicated in the spontaneous clearance of hepatitis C virus (HCV) after acute infection. The aim of this study was to determine the epidemiological factors that predict the resolution of acute HCV infection without therapy in patients with human immunodeficiency virus (HIV) infection.', 'We conducted a retrospective, multivariate analysis of epidemiological data from HIV-infected patients presenting from 2000 to 2007 with evidence of past or present HCV infection. Data were collected from one American and two European HIV treatment clinics. A final cohort of 769 HIV-infected patients referred for treatment with available test results for antibody to HCV, HCV RNA, and hepatitis B surface antigen were included for the analysis. We calculated spontaneous clearance rates based on race, geographical location, gender, transmission risk factors, and hepatitis B virus coinfection.', 'Patients who admitted to a history of injection drug use spontaneously cleared the HCV infection significantly less often (11.6%) than those in whom sexual transmission was the presumed route of HCV infection (21.9%) (p=0.004). This difference was more pronounced when heterosexual contact as the source of infection was analyzed separately. Multivariate analysis identified heterosexual HCV transmission (OR 2.81, 95% CI 1.55-5.09) and hepatitis B surface antigen carrier status (OR 10.3, 95% CI 4.29-24.73) as independent factors predicting spontaneous HCV clearance. No differences according to gender, race or geographical origin were observed.'] Is sexual transmission associated with spontaneous HCV clearance in HIV-infected patients?