Danish Study Looks at Hepatitis C Sexual Transmission among HIV Positive Gay Men

Less than 1% of HIV positive gay and bisexual men seen at a Danish hospital were found to have acute hepatitis C virus (HCV) infection, according to a study presented at the American Association for the Study of Liver Diseases "Liver Meeting" (AASLD 2010) this week in Boston. All those who started hepatitis C treatment within 6 months of becoming infected achieved rapid virological response, while 1 who started later experienced HCV relapse.

Starting around 2000, clinicians in large Europe cities began reporting outbreaks of acute HCV infection among HIV positive men who have sex with men (MSM). Numerous studies showed that these cases -- and similar ones in Australia and the U.S. -- were clustered within sexual networks. A variety of risk factors have been identified, including fisting, unprotected anal sex, non-injection drug use, and sex at public venues, but these have not been consistent across studies.

In the present study, researchers sought to shed further light on the incidence of sexually transmitted acute hepatitis C among HIV positive MSM in a Danish cohort, and to describe factors associated with HCV diagnosis and its clinical manifestations.

Investigators analyzed data from all 871 HIV positive MSM (out of more than 1800 total HIV patients) who were seen at least once at the infectious disease clinic at Rigshospitalet in Copenhagen and enrolled in the Danish HIV Cohort during a 4-year period spanning January 2005 through December 2009.

Men were considered to have acute hepatitis C if they tested HCV negative at the beginning of 2005 but became positive -- according to antibody and HCV RNA assays -- during the 4-year study period. Cases were identified through the national HIV database, supplemented with the most recent cases identified by treating physicians. People who reported drug use were excluded from this analysis.

Results

• 41 HIV positive gay/bisexual men had hepatitis C, 14 of whom were found to be newly infected during the study period.
• Only 1 such individual was excluded due to drug use.
• This yielded 13 cases per 871 patients during a 4-year period, for an incidence rate of approximately 0.37% per year.
• The number of detected cases increased over time, from 1 in 2006, to 4 in 2007, to 3 in 2008, to 5 in 2009.
• Most patients (9 out of 13) were tested due to unexplained liver enzyme elevation; only 3 were symptomatic for hepatitis.
• The median age at the time of HCV infection was 41 years.
• Men with acute HCV had generally well-preserved immune function, with a media CD4 count of 610 cells/mm3 (range 300-1400 cells/mm3).
• 5 men with acute hepatitis C were diagnosed with other sexually transmitted diseases during the study period (2 with syphilis, 3 with chlamydia).
• Most men (10 out of 13) had hard-to-treat HCV genotype 1 (the rest had unknown genotype).
• 5 men were treated for hepatitis C; all 4 who started treatment within 6 months after HCV infection experienced rapid virological response (RVR) -- a predictive factor for sustained virological response (SVR):

• 2 with RVR, or undetectable HCV RNA after 4 months of therapy, still being followed for longer-term outcomes;
• 1 with RVR at week 4 and continued undetectable HCV RNA at the end of treatment.
• 1 with RVR and SVR, or continued undetectable HCV RNA 6 months after completing treatment.
• 1 did not achieve RVR and subsequently experienced HCV relapse.
• Among the 8 men who were not treated, 3 experienced spontaneous HCV clearance and 5 developed persistent or chronic infection.

"We found an incidence of 0.4% of sexually transmitted HCV among HIV positive MSM, which is comparable to the incidence rates found in other Western countries," the investigators concluded.

They added that these findings "suggest a need for safer sex practices" among MSM with discordant (1 positive, 1 negative) HCV status, and "underscores the need for HCV testing when unexplained liver function tests are observed."

Most cases of apparently sexually transmitted HCV among gay/bisexual men have been people with HIV. Some experts have suggested this might be due to the fact that HIV positive people receive regular liver function tests to monitor for antiretroviral drug toxicity, which can catch liver problems during acute HCV infection. Acute hepatitis C often has no symptoms -- or ones easily mistaken for a flu -- so most people otherwise are not diagnosed this early. The few studies that have tested all MSM at sexual health clinics, however, have still detected acute HCV mostly in HIV positive men.

11/5/10

Reference

TS Barfod, LH Omland, and TL Katzenstein. Incidence and characteristics of sexually transmitted acute hepatitis C virus infection among HIV-positive MSM in Copenhagen, Denmark during four years (2006-2009). A retrospective cohort study. 61st Annual Meeting of the American Association for the Study of Liver Diseases (AASLD 2010). Boston, October 29-November 2, 2010. Abstract 753.