Hepatitis C is a common infection worldwide, but acute infection is often asymptomatic and difficult to diagnose. People coinfected with HIV and hepatitis C might progress to chronic liver disease more quickly. We present a case of a man infected with HIV with sexually acquired acute hepatitis C and discuss the immunology, natural history, and epidemiology of acute hepatitis C and coinfection with HIV. Several recent reports have documented acute hepatitis C among men who have sex with men who engage in high risk sexual practices and often have concomitant genital ulcer disease. We review treatment options for the medical management of acute hepatitis C and coinfection with HIV. © 2009 Elsevier Ltd. All rights reserved.