Can J Gastroenterol Hepatol. 2015 Nov-Dec;29(8):e1-6. doi: 10.1155/2015/940825. Epub 2015 Sep 24.
Hepatitis B virus (HBV) precore (PC) and basal core promoter (BCP) variants are well known; however, their prevalence in North America is unclear, especially among hepatitis B e antigen-negative patients.
To investigate the prevalence of PC⁄BCP mutations and their clinical significance.
One hundred twenty-eight patients positive for both hepatitis B surface antigen and hepatitis B e antibody were selected, and PC⁄BCP mutations were identified using a line probe assay. The subjects' charts were reviewed for race⁄ethnicity, HBV genotype, HBV viral load, sex, liver enzyme levels, imaging and biopsy results up to 10 years before the study.
The prevalence of PC and BCP variants were 47.6% and 62.5%, respectively. Older age was associated with aspartate aminotransferase-to-platelet index ratio (APRI) ≥0.7 (P=0.011) and abnormal imaging⁄biopsy results (P=0.0008). Although the presence of BCP variant(s) was associated with APRI ≥0.7 (P=0.029), it was not associated with abnormal imaging⁄biopsy results. The combination of age ≥50 years and the presence of BCP variant(s) was associated with abnormal imaging⁄biopsy results, suggestive of either cirrhosis or hepatocellular carcinoma (not observed with PC mutation). Neither sex or genotype, or median HBV viral load showed significant influence on any of these outcomes.
The present study suggests that the prevalence of PC and BCP mutations are higher than what has been previously reported. One potential explanation would be increased immigration in the past decade. Considering the potential public health and clinical implications of these variants, long-term multicentre and prospective studies could further unravel the uncertainty around these variants.
乙型肝炎病毒（HBV）前核心（PC）和基本核心启动子（BCP）变异体广为人知；然而，它们在北美的流行情况尚不清楚，尤其是在乙型肝炎 e 抗原阴性患者中。
研究 PC/BCP 突变的流行情况及其临床意义。
选择 128 例乙型肝炎表面抗原和乙型肝炎 e 抗体均阳性的患者，采用线性探针检测法鉴定 PC/BCP 突变。回顾性分析患者的病历，内容包括种族/民族、HBV 基因型、HBV 病毒载量、性别、肝酶水平、研究前 10 年内的影像学和活检结果。
PC 和 BCP 变异体的流行率分别为 47.6%和 62.5%。年龄较大与天门冬氨酸氨基转移酶-血小板指数比值（APRI）≥0.7（P=0.011）和影像学/活检异常结果（P=0.0008）相关。尽管 BCP 变异体的存在与 APRI≥0.7（P=0.029）相关，但与影像学/活检异常结果无关。年龄≥50 岁和 BCP 变异体的存在的组合与影像学/活检异常结果相关，提示存在肝硬化或肝细胞癌（未观察到 PC 突变）。性别或基因型，或中位 HBV 病毒载量均未对上述任何结果产生显著影响。
本研究表明，PC 和 BCP 突变的流行率高于以往报道。一个可能的解释是过去十年移民增加。考虑到这些变异体的潜在公共卫生和临床意义，长期的多中心和前瞻性研究可以进一步阐明这些变异体的不确定性。
