Hepatitis B Virus Prevalence and Vaccine Response in HIV-infected Children and Adolescents on Combination Antiretroviral Therapy in Kigali, Rwanda

OBJECTIVE: The aim of this study was to determine the prevalence of hepatitis B virus (HBV) infection in a cohort of HIV-infected Rwandan children and adolescents on combination antiretroviral therapy (cART), and the success rate of HBV vaccination in those children found to be HBV negative. METHODS: HIV-infected children and adolescents (age 8-17 years) receiving cART with CD4 T-cells count ≥200 cells/mm and/or ≥15% and without prior HBV vaccination (by history, vaccination cards and clinic records) underwent serologic testing for past (negative HBV surface antigen [HBsAg] with positive antibody to HBV core antigen [cAb] and to HBsAg [anti-HBs]) or active HBV infection (positive HBsAg). Children with any positive HBV serologic tests were excluded from further vaccination; all others completed 3 HBV immunizations with 10 µg of ENGERIX-B. Anti-HBs titer was measured 4-6 weeks after the last immunization. RESULTS: Of 88 children, 6 (7%) children had active HBV infection and 8 (9%) had past HBV infection. The median (interquartile range) age, CD4 T-cell count and cART duration were 12.3 (10.1-13.9) years, 626 (503 to 942) cells/mm and 1.9 (1.5-2.7) years, respectively. Seventeen children had detectable plasma HIV-1 RNA. Seventy-3 children completed 3 immunizations with median (interquartile range) postimmunization anti-HBs concentration of 151 mIU/mL (1.03-650). Overall, 52 children (71%, 95% confidence interval: 61-82) developed a protective anti-HBs response. HIV-1 RNA and CD4 T-cell count were independent predictors of a protective anti-HBs response. Protective anti-HBs response was achieved in 82% of children with undetectable HIV-1 RNA and 77% with CD4 T cells ≥350/mm. CONCLUSIONS: The substantial HBV prevalence in this cohort suggests that HIV-infected Rwandan children should be screened for HBV before cART initiation. HIV viral suppression and CD4 T cells ≥350/mm favored the likelihood of a protective response after HBV vaccination.