Background:  Hepatitis C virus (HCV) is an emerging infection among HIV-infected men who have sex with men (MSM). These men are unusual in that they acquired HCV after they acquired HIV, whereas HCV is typically acquired first. Because individuals who are immunocompromised at the time they acquire HCV often progress to end stage liver disease in as few as 3 years, these HIV-infected men with acute HCV are potentially at high risk for rapidly progressive liver injury.

Methods:  We performed a prospective cohort study of HIV-infected MSM with acute HCV infection to evaluate liver histology and risk factors for acquisition of HCV. Acute HCV infection was diagnosed using a combination of 3 criteria:  HCV antibody seroconversion, alanine aminotransferase (ALT) elevation to >10-fold over the upper limit of normal, and wide fluctuation in HCV viral load, a hallmark of the acute phase of HCV infection. Fibrosis progression rate (FPR) was calculated by dividing the fibrosis stage by the interval between the date of the new ALT elevation and the date of the biopsy.

Results: Of the 11 patients who underwent liver biopsy, 9 did so within 4½ months of the detection of ALT elevation, and 2 within 16 months. Despite the short duration of HCV infection, 9 of 11 patients (82%) had stage 2 fibrosis (Scheuer, scale 0 to 4) and 1 had stage 1 fibrosis. The mean FPR in these 11 patients was 4.5±3.3 units per year (see the figure). No cause of liver damage other than acute HCV infection was identified. In the analysis of risk factors for HCV acquisition, only 4 patients reported even a single episode of intravenous drug use (IDU). In contrast, non-IDU and high-risk sexual behavior were common: 7 reported "club" drug use, including methamphetamine, and 10 reported unprotected anal intercourse with multiple partners.

Conclusions:  Acute HCV infection of MSM with underlying HIV infection resulted in early and rapid progression of liver fibrosis, with FPR rates far in excess of other settings of HCV infection. Many of these HIV-infected men with acute HCV used non-injection drugs and had unprotected sex with multiple partners. Some appear to have become HCV-infected via sexual activity. More intensive prevention and screening strategies for acute HCV in MSM are needed. In addition, further research is needed to identify the disease processes leading to this highly accelerated liver injury.