National Institute of Science and Technology for Health Technology Assessment, Rua Dr. Freire Alemao 351 /703, Porto Alegre, RS, Brazil.
Braz J Infect Dis. 2011 Mar-Apr;15(2):159-62.
Occult hepatitis B virus (HBV) infection is characterized by the detection of HBV DNA in serum and/or in liver in the absence of detectable hepatitis B surface antigen (HBsAg). The reported prevalence of occult hepatitis B varies markedly among populations and according to the sensitivity of the HBV DNA assay. The aim of the present study was to describe the prevalence of occult hepatitis B among HCV-infected and non-infected blood donors in Porto Alegre, Southern Brazil, using a highly sensitive real time polymerase chain reaction (PCR) method.
Between 1995 and 1997 a sample of 178 blood donors with two positive anti-HCV ELISA tests were consecutively selected as cases, and 356 anti-HCV negative donors were selected as controls. Blood donors were randomly selected from eight blood centers in Porto Alegre, Southern Brazil, representative of the whole blood donor population. Blood samples were kept at 70ºC and defrosted for the first time for the analysis of this report. Tests previously performed in the laboratory using the same real time PCR for HBV DNA had sensitivity for detecting as low as 9 copies/mL. Among 158 blood samples from HBsAg-negative blood donors, five were anti-HBc positive, 53 tested positive for anti-HCV and 105 had anti-HCV negative. The samples analysis was performed in duplicate and all blood samples tested negative for HBV DNA.
The result reflects a very low prevalence of occult hepatitis B in our setting.
隐匿性乙型肝炎病毒（HBV）感染的特征是血清和/或肝脏中可检测到 HBV DNA，但无法检测到乙型肝炎表面抗原（HBsAg）。隐匿性乙型肝炎的报告患病率在不同人群和根据 HBV DNA 检测的灵敏度而有很大差异。本研究的目的是使用高度敏感的实时聚合酶链反应（PCR）方法，描述巴西南部阿雷格里港 HCV 感染和非感染献血者中隐匿性乙型肝炎的患病率。
1995 年至 1997 年，连续选择了 178 名抗 HCV ELISA 测试呈阳性的献血者作为病例，选择了 356 名抗 HCV 阴性的献血者作为对照。献血者是从巴西南部阿雷格里港的八个血液中心随机选择的，代表了整个献血者人群。血液样本在 70°C 下保存，并在第一次解冻时用于本报告的分析。实验室中之前使用相同的实时 PCR 检测 HBV DNA 的检测方法具有检测低至 9 拷贝/ml 的灵敏度。在 158 名 HBsAg 阴性献血者的血液样本中，有 5 份抗 HBc 阳性，53 份抗 HCV 阳性，105 份抗 HCV 阴性。对样本进行了重复分析，所有血液样本均未检测到 HBV DNA。
该结果反映了我们研究环境中隐匿性乙型肝炎的患病率非常低。
