LAUSR

Little data exist on basal core promoter/precore (BCP/PC) mutations in chronic hepatitis B (CHB) patients at the immune‐tolerance (IT) phase. We studied consecutive treatment‐naïve, CHBe‐antigen (HBeAg)‐positive patients who had undergone liver biopsy and genotyping. Those in the IT phase or immune‐clearance (IC) phase were enrolled for comparison of the frequency of BCP/PC mutations and their clinical presentations. Subgroup analyses for the IT group were also performed between patients with and without mutations, and IC patients between fibrosis stages ≤2 vs fibrosis >2. Among 301 patients enrolled, 88/301 (29.24%) and 213/301 (70.76%) were at the IT and IC phase, respectively. The frequency of BCP/PC mutations in IT phase was significantly lower than those in IC phase (15.91% vs 64.79%, P < .001). The BCP mutation only was significantly more frequent than the PC mutation in both groups and also in all IC subgroups. IT patients with BCP/PC mutations had significantly higher quantitative anti‐HBc levels compared with those of patients with wild‐type virus (P < .05). They also had significantly lower mean levels of alanine transaminase, aspartate transaminase, total bilirubin and qAnti‐HBc compared with those of IC patients (all P < .05). Additionally, they were significantly younger in mean age, had higher platelet count, higher levels of HBV DNA and surface antigen, as well as higher frequency of genotype B than those of IC patients with fibrosis >2 (all P < .05). BCP/PC mutations were found in IT patients with CHB. They had distinct clinical characteristics when compared with patients with wild‐type or at IC phase. Further studies are needed to understand their natural history and treatment outcomes.