Factors associated with clearance of hepatitis B virus surface antigen in patients infected with human immunodeficiency virus

Owing to similar routes of transmission, hepatitis B virus (HBV) and human immunodeficiency virus (HIV) coinfection commonly occurs. Compared with patients infected with only HBV, coinfected patients develop persistent HBV infection followed by advanced liver diseases. However, the characteristics of HIV-infected patients who can achieve the clearance of HBV surface antigen (HBsAg) have not been clarified. In this study, we retrospectively examined patients coinfected with HBV and HIV and determined the host factors associated with HBsAg clearance. Among HIV-infected patients who visited our hospital between 1994 and 2017, we examined medical records of those who were seropositive for HBsAg at least once. Among them, patients who cleared HBsAg afterward were regarded as “cured,” while those who remained HBsAg-seropositive until 2017 were “chronic.” HBsAg seropositivity was found in 57 patients, and among them, 27 male patients were cured whereas 18 were chronic. The cured patients were significantly younger and had higher CD4 cell and platelet counts than the chronic patients. In addition, the cured patients had higher levels of transaminases after the detection of HBsAg. Multivariate analysis revealed age as an independent factor. Analyses of the patients infected with genotype A also showed that the cured patients had significantly higher CD4 cell counts. Considering that the CD4 cell and platelet counts were higher in the cured patients, immunological and liver functions were closely associated with HBsAg clearance. Higher levels of transaminases in the cured patients may also reflect the immunological function leading to HBsAg clearance.