HCV and HIV: a tale of two viruses.

Liver disease has emerged as a major cause of morbidity and mortality in patients infected with the human immunodeficiency virus. Hepatic injury is highly associated with hepatitis C virus (HCV) infection, though hepatitis B virus and drug-induced hepatotoxicity are also important cofactors. HCV coinfection is linked to increased hepatic fibrosis progression, leading to development of cirrhosis and liver failure earlier than in HCV monoinfected patients. Initiation of highly active antiretroviral treatment regimens may paradoxically increase HCV loads. Some data suggest that HCV coinfection may hasten progression of AIDS, but this remains controversial. Three major randomized clinical trials demonstrate improved efficacy of peginterferon with ribavirin for treatment of HCV in coinfected subjects compared to those with HCV alone. However, response rates are lower than those observed in patients with HCV monoinfection. Sustained virologic response rates of 27% to 40% are reported.