François M, Dubois F, Brand D, Bacq Y, Guerois C, Mouchet C, Tichet J, Goudeau A, Barin F
Département de Microbiologie Médicale et Moléculaire, URA 1334, Centre Hospitalier Universitaire Bretonneau, Tours, France.
J Clin Microbiol. 1993 May;31(5):1189-93. doi: 10.1128/jcm.31.5.1189-1193.1993.
Hepatitis C virus (HCV) infection is currently assessed by detection of antibodies to HCV with immunoassays. However, in the absence of an in vitro system to isolate the virus, or an immunoassay to identify HCV antigen in blood, an ongoing acute or chronic HCV infection can be diagnosed only by detection of HCV RNA by polymerase chain reaction. We used a reverse transcription-nested polymerase chain reaction to detect an HCV 5' noncoding viral RNA sequence in serum specimens collected from anti-HCV-positive individuals belonging to different risk groups and compared the results with those obtained with a prototype recombinant immunoblot assay (Chiron HCV SIA prototype recombinant immunoblot assay [RIBA]) containing four different viral peptides (c22, c33c, c100, and NS5). The prevalence of HCV viremia ranged from 25.9% in HCV antibody-positive blood donors to 92% in HCV antibody-positive hemophiliacs. Elevated alanine aminotransferase values in HCV antibody-positive patients were clearly associated with viremia. Ninety-six percent of HCV RNA-positive patients reacted to two viral antigens or more, compared with only 64% of HCV RNA-negative patients. Contrary to previous reports, HCV viremia was not associated with either the presence or the absence of a particular antibody specificity. The newly introduced NS5 peptide did not improve the sensitivity or specificity of the RIBA. Although 20% of the patients in our study whose sera reacted to all of the antigens were HCV RNA negative, the positive predictive value of a RIBA considered positive by the manufacturer (two or more bands), was rather high (78%) and may allow suspicion of viremia in EIA2 enzyme-linked immunosorbent assay-positive patients.
目前，丙型肝炎病毒（HCV）感染是通过免疫测定法检测抗HCV抗体来评估的。然而，由于缺乏体外分离病毒的系统，也没有用于识别血液中HCV抗原的免疫测定法，正在进行的急性或慢性HCV感染只能通过聚合酶链反应检测HCV RNA来诊断。我们使用逆转录巢式聚合酶链反应来检测从属于不同风险组的抗HCV阳性个体采集的血清标本中的HCV 5'非编码病毒RNA序列，并将结果与使用包含四种不同病毒肽（c22、c33c、c100和NS5）的原型重组免疫印迹测定法（Chiron HCV SIA原型重组免疫印迹测定法[RIBA]）获得的结果进行比较。HCV病毒血症的患病率在HCV抗体阳性献血者中为25.9%，在HCV抗体阳性血友病患者中为92%。HCV抗体阳性患者丙氨酸转氨酶值升高与病毒血症明显相关。96%的HCV RNA阳性患者对两种或更多种病毒抗原产生反应，而HCV RNA阴性患者中这一比例仅为64%。与先前的报道相反，HCV病毒血症与特定抗体特异性的存在与否均无关。新引入的NS5肽并未提高RIBA的敏感性或特异性。尽管在我们的研究中，20%血清对所有抗原均有反应的患者HCV RNA为阴性，但制造商认定为阳性（两条或更多条带）的RIBA的阳性预测值相当高（78%），这可能使酶联免疫吸附测定法（EIA2）阳性患者的病毒血症受到怀疑。
