Department of Medicine and Geriatrics, United Christian Hospital, Hong Kong.
J Clin Virol. 2010 Feb;47(2):193-5. doi: 10.1016/j.jcv.2009.11.024. Epub 2009 Dec 23.
In patients with occult hepatitis B virus (HBV) infection, acute exacerbation may occur when they become immunocompromised. Usually, these patients develop hepatitis B surface antigen (HBsAg) seroreversion during the flare. Here we report on a patient with occult HBV infection, who developed HBV exacerbation after chemotherapy for diffuse large B-cell lymphoma. The resurgence of HBV DNA preceded the elevation of liver enzymes for 20 weeks. Atypically, despite high viraemia, serological tests showed persistently negative HBsAg using three different sensitive HBsAg assays (i.e., Architect, Murex and AxSYM). On comparing the amino acid sequence of the index patient with the consensus sequence, five mutations were found at pre-S1, five at pre-S2 and twenty-three mutations at the S region. Six amino acid mutations were located in the 'a' determinant, including P120T, K122R, M133T, F134L, D144A and G145A. The mutants K122R, F134L and G145A in our patient have not been tested for their sensitivity to Architect and Murex assays by the previous investigators and might represent the escape mutants to these assays.
在隐匿性乙型肝炎病毒 (HBV) 感染患者中，当他们免疫功能低下时可能会发生急性恶化。通常，这些患者在发作期间会出现乙型肝炎表面抗原 (HBsAg) 血清学转换。在这里，我们报告了一例隐匿性 HBV 感染患者，他在接受弥漫性大 B 细胞淋巴瘤化疗后发生了 HBV 恶化。HBV DNA 的回升先于肝酶升高 20 周。异常的是，尽管病毒载量很高，但使用三种不同的敏感 HBsAg 检测方法（即 Architect、Murex 和 AxSYM），血清学检测仍持续显示 HBsAg 阴性。在比较指数患者的氨基酸序列与共识序列后，在 pre-S1 区发现了 5 个突变，在 pre-S2 区发现了 5 个突变，在 S 区发现了 23 个突变。6 个氨基酸突变位于 'a' 决定簇，包括 P120T、K122R、M133T、F134L、D144A 和 G145A。我们的患者中的突变体 K122R、F134L 和 G145A 尚未被之前的研究人员测试过对 Architect 和 Murex 检测的敏感性，它们可能代表对这些检测的逃逸突变体。
