Baseline Level of Hepatitis B Core Antibody Predicts Spontaneous Hepatitis B e Antigen (HBeAg) Seroconversion in HBeAg-Positive Children With a Normal Alanine Aminotransferase Level.

It is not clear whether baseline hepatitis B core antibody (anti-HBc) level in hepatitis B e antigen (HBeAg)-positive children with a normal alanine aminotransferase (ALT) level is predictive of spontaneous HBeAg seroconversion. We investigated the correlation between anti-HBc level and the natural course of chronic hepatitis B (CHB) virus (HBV) infection in children, particularly the ability of baseline anti-HBc level to predict spontaneous HBeAg seroconversion during long-term follow-up. HBeAg-positive children with untreated CHB and a normal ALT level were followed longitudinally. Anti-HBc level was determined by double-sandwich immunoassay. Effects of anti-HBc levels and other parameters on spontaneous HBeAg seroconversion and the natural course of CHB were assessed. A total of 182 children (106 males) with a median age at enrollment of 10.6 years (interquartile range [IQR], 10.3-15.3) were followed for a median of 19.8 years (IQR, 11.9-21.9). Spontaneous HBeAg seroconversion occurred in 85 children (46.7%) during the follow-up. A baseline anti-HBc titer of >500 IU/mL (hazard ratio [HR] = 2.81), HBV genotype B and B + C (HR = 3.46), and a baseline hepatitis B surface antigen titer of ≤4.8 log10  IU/mL (HR = 3.09) were predictive of spontaneous HBeAg seroconversion, based on multivariable survival analysis (P < 0.001). In cases remaining HBeAg positive, their anti-HBc levels increased gradually during follow-up because of ongoing inflammation. Conclusion: Baseline anti-HBc level is predictive of spontaneous HBeAg seroconversion in HBeAg-positive children with a normal ALT level. Anti-HBc level reflects anti-HBV immune response in the HBeAg-positive normal ALT phase of CHB.