Hepatitis C virus infections among HIV-infected men who have sex with men: an expanding epidemic.

BACKGROUND: Since 2000 outbreaks of sexually transmitted hepatitis C Virus (HCV) infections have been reported among HIV-infected men who have sex with men (MSM). We studied the prevalence and determinants of HCV-infection among MSM attending a large sexually transmitted infection (STI) clinic in the Netherlands. METHODS: In 2007-2008, 3125 attendees of the STI clinic Amsterdam, including 689 MSM, participated in an anonymous biannual crosssectional survey. Participants were interviewed and screened for HIV and HCV antibodies. Additionally, all anti-HCV positive and HIV-infected individuals were tested for HCV RNA. Using phylogenetic analysis, HCV strains of the STI clinic attendees were compared with those isolated from MSM with acute HCV in 2000-2007. Determinants of HCV-infection were analysed using logistic regression. RESULTS: Two of 532 (0.4%) HIV-negative MSM and 28 of 157 (17.8%) HIV-positive MSM were infected with HCV. Over the study period, HCV prevalence among HIV-infected MSM increased (14.6%-20.9%). Seven of 28 (25.0%) HIV/HCV coinfected MSM had acute HCV infection. Only five of 28 (17.9%) HIV/HCV coinfected MSM ever injected drugs (IDU). HIV-infection, IDU, fisting and gamma hydroxy butyrate (GHB)-use were significantly associated with HCV-infection. Phylogenetic analyses revealed a high degree of MSM-specific clustering. CONCLUSION: We found a high and increasing HCV prevalence in HIV-infected MSM. Though not statistically significant, this trend, and the relatively large proportion of acute infections suggest ongoing transmission of HCV in HIV-positive MSM. Regardless of IDU, rough sexual techniques and use of recreational drugs were associated with HCV-infection; phylogenetic analysis supported sexual transmission. Targeted prevention, like raising awareness and routine testing, is needed to stop the further spread among HIV-infected MSM, and to prevent possible spillover to HIV-negative MSM.