As treatment with direct-acting antivirals (DAAs) can lead to reactivation of hepatitis B virus (HBV), testing for HBV DNA along with hepatitis B core antibodies (anti-HBc) in men who have sex with men (MSM) and people who use drugs (PWUD) co-infected with hepatitis C virus (HCV) is warranted prior to DAA treatment, according to a study published in the Journal of Viral Hepatitis.
High rates (approximately 25%) of chronic HBV infection have been observed in PWUD and MSM, therefore researchers sought to estimate the frequency of delayed hepatitis B surface antigen (HBsAg) seroclearance, along with its determinants and time to delayed HBsAg seroclearance.
Using data from MSM and PWUD enrolled in the Amsterdam Cohort Studies (1985-2002) who had anti-HBc seroconversion, they found that 147 incident HBV infections occurred during follow-up. On initial HBsAg testing after infection (6-12 months), 42 (29%) were HBsAg positive and 105 (71%) were HBsAg negative. Of these 42 initially 42 HBsAg-positive patients, 22 subsequently tested HBsAg negative. Overall, 15 became HBsAg negative and HBV-DNA negative, while 27 remained HBsAg and/or HBV-DNA positive (“chronic HBV”). Thus, the 5-year cumulative probability of delayed HBsAg seroclearance was 41.6% for initially HBsAg-positive patients.
“In conclusion, more than one-third of adult MSM and PWUD were able to spontaneously clear HBsAg within five years after established chronic HBV infection, yet a higher proportion of HBV chronicity (~18%) was observed in this population compared to the general population (~5%),” stated the investigators. They added that, “The latter finding highlights the importance of prompt HBV vaccination in these key populations.”
van Santen DK, Boyd A, Bruisten S, Sonder GJB, Prins M, van Houdt R. Frequent delayed spontaneous seroclearance of hepatitis B virus after incident HBV infection among adult high-risk groups [published online September 13, 2019]. J Viral Hepat. doi:10.1111/jvh.13205