关键词: 丙型肝炎病毒, 抗体, 假阴性率, 窗口期

Abstract:

Objective To investigate the causes and disposal scheme for grey zone samples of anti-hepatitis C virus（HCV） antibody determination. Methods Anti-HCV antibody were determined by 5 domestic kits [4 kits using indirect enzyme-linked immunosorbent assay（ELISA） and 1 kit using double antigen sandwich method] and 1 imported kit using chemiluminescence immunoassay. Samples with inconsistent results were further determined by recombinant immunoblot assay（RIBA）. Then,real-time fluorescence quantitation polymerase chain reaction（PCR） was used to determine indeterminate samples for HCV RNA in RIBA. A total of 12 samples in window period were determined by HCV RNA for copies and genotypes. Results Except kit F,the other 5 kits showed review negative coincidence rates ≥ 90%. Review positive coincidence rates were increased with the increasing of initial S/CO ratio. When S/CO ratio was >15.01,6 kits showed review positive coincidence rates > 95%. The false negative rates of single 1 kit were 27.8%-94.4%. The false negative rates of 2 domestic kits randomly were 8.3%-61.1%,the false negative rates of 2 domestic kits randomly with 1 imported kit were 5.6% -22.2%,and the false negative rates of 2 domestic kits randomly using indirect ELISA with 1 domestic kit using double antigen sandwich method were 2.2%-13.9%. The results of 12 samples in window period by 6 kits were negative or positive partly in grey zone,the results by RIBA were negative or indeterminate,and the results for HCV RNA was weakly positive. The 8 of 12 samples in window period were genotype 1b,and the other 4 samples had no genotype. Conclusions When the results are in grey zone,it should use at least 2 different kits for reviewing. Kit using double antigen sandwich method or imported kit can be introduced for supplement. In order to reduce the missing determination of samples in window period,it suggests that HCV RNA determination can be used as supplement.

Key words: Hepatitis C virus, Antibody, False negative rate, Window period