OBJECTIVETo investigate the correlation between viral factors and liver histological changes of HBeAg-negative chronic hepatitis B patients with persistently normal serum ALT levels (PNAL).

METHODSHBV DNA level, HBV genotype, basal core promoter (BCP) and precore mutation were examined in 52 HBeAg-negative chronic hepatitis B patients with PNAL (defined as normal ALT measured on at least 3 occasions in the intervals of about two months over a period of 12 months or more prior to the biopsy).

RESULTSSubjects with both BCP and precore mutations had significantly higher HBV DNA levels than those without mutations [(4.9+/-1.4) vs (4.1+/-1.1) log(10)copies/ml, t = 2.308, P < 0.05]. A higher proportion of patients with histological activity index (HAI) > or = to 4 was found in patients with both mutations (32.1% vs 16.7%) than in patients without mutation, however, the proportion of patients with histological activity index (HAI) > or = to 3 in patients with mutations was not significantly different from that in patients without mutations (14.3% vs. 12.5%, x(2)=0.000, P > 0.05). In patients without precore or BCP mutations, there was a strong positive correlation between viral load and liver inflammation as well as fibrosis (precore: r=0.626, 0.592, P < 0.01; BCP: r=0.730, 0.641, P < 0.01). In patients without both mutations, HBV DNA has shown a high accuracy for predecting fibrosis (F > or = 3) (AUC = 0.905, 95% CI: 0.771-1.039, P < 0.05) with the cutoff value of 4.5 log(10) copies/ml (sensitivity = 1.000, specificity = 0.778, PPV = 42.9%, NPV = 100.0%). Results of both genotypes and mutations were successfully obtained in 40 samples with HBV DNA is > or = to 10(4) copies/ml. The higher viral load was observed in the patients with genotype B than genotype C (5.1 vs 4.3 log(10)copies/ml, t = 2.059, P < 0.05), but no difference was seen of liver pathologic changes between these two genotypes.

CONCLUSIONSVirus harboring both BCP and precore mutants has the higher replication level than wild type virus. 32.1% and 14.3% of the patients with both mutations have moderate or severe inflammation and fibrosis. There was a strong positive correlation between viral load and liver histological changes in patients without precore or BCP mutations, and viral load shows a high accuracy for predecting significant fibrosis (F > or = 3).