Detection of hepatitis B virus in cerebrospinal fluid of people with HIV-associated cryptococcal meningitis in Botswana

OBJECTIVES: To investigate hepatitis B virus presence in plasma and cerebrospinal fluid (CSF) of people living with HIV (PLWH) associated cryptococcal meningitis (CM) in Botswana. METHODS: Baseline plasma and CSF samples from the AMBIsome Therapy Induction Optimization for CM study, which enrolled adult PLWH with CM in Botswana (2018-2021), were screened for HBV surface antigen (HBsAg), viral load, occult hepatitis B infection (HBsAg- and HBV DNA+), and sequenced the surface/polymerase region to assess mutations and genetic diversity. RESULTS: Among 81 participants, 67.9% (55/81) were male, median age was 40 years (IQR: 34-44), median CD4+ T cell count was 29 cells/µl (IQR: 11-65). Available plasma (n = 77) and CSF (n = 74) samples were screened for HBV. Plasma HBsAg prevalence was 29.7% (95% CI: 20-42 (19/64) and 18.8% (95% CI: 10-30 (13/69) in CSF. Occult HBV infection (HBsAg- and HBV DNA+) was detected in 35.5% (95% CI: 21-53, 11/31) in plasma and 2.4% (95% CI: 0.06-13, 1/42) in CSF. ART exposure was associated with reduced plasma HBV DNA (P = 0.04), with no significant effect observed in CSF (P = 0.7). In plasma-CSF pairs, plasma showed higher detection rates for HBsAg, HBV DNA, and OBI (P ≤ 0.01). HBV was sequenced in 5 CSF and 4 plasma samples, including 3 pairs. Genotypes A and D detected were concordant between pairs, but 2 pairs showed mutational frequency discordance. CONCLUSION: HBsAg and HBV DNA were detected in CSF of PLWH with CM, suggesting the CSF may be a reservoir.