Long-term clinical impact of occult hepatitis B virus infection in chronic hepatitis B patients

Background/Aims: Long-term clinical outcomes of occult hepatitis B virus (HBV) infection were studied. Methods: Fifteen chronic hepatitis B patients were monitored for a median of 4.4 years (range 0.9–15.3) after hepatitis B surface antigen (HBsAg) seroclearance. Serum HBV DNA was measured by real-time detection polymerase chain reaction. Thirteen patients underwent liver biopsies at the end of follow-up and liver histology was evaluated by Ishak score. Liver HBV DNA was also measured for 12 patients. Results: At the end of follow-up, HBV viremia was absent in 13 (87%) patients, and antibody titers to hepatitis B core antigen showed an inverse correlation with time from HBsAg seroclearance (r=−0.554; P=0.0040). However, all patients retained liver HBV DNA and tested positive for the covalently closed circular HBV DNA replicative intermediate. The hepatic HBV DNA loads had no relation to liver histology. Paired biopsies from 11 patients disclosed that each necroinflammatory score significantly improved after HBsAg seroclearance. Amelioration of liver fibrosis was also evident in eight (73%) patients (P=0.0391 by signed rank test). Conclusions: A long-standing but strongly suppressed HBV infection may confer histological amelioration after HBsAg seroclearance.