A study on optimizing reporting process for hepatitis C virus antibody test for blood donors in blood center′ laboratory

Objective To assess the accuracy of indirect enzyme- linked immunosorbent assay( ELISA) for hepatitis C virus( HCV) antibody as a routine test in the blood center,discuss how to optimize the reporting process for HCV antibody,and protect donors' enthusiasm and precious blood resources. Methods A total of 116 samples were screened by two indirect anti- HCV ELISA kits available from Shanghai Kehua( reagent A) and Beijing Wantai( reagent B),respectively. Samples that yielded positive results or gray- zone results were further validated using a confirmation reagent to establish definitive results and compare confirmed positive results and the results with the two reagents for indirect ELISA. Differences in the ELISA results of the 116 samples between the two anti- HCV reagents were compared using the paired chi- square test and the agreement between the results with the two reagents were compared using the Kappa test. Results There were significant differences in the test results between the two reagents used for indirect ELISA( P = 0. 04),but the two reagents varied greatly from each other. The false positive rates of samples strongly or weakly positive with both reagents were 0 and 35. 7%,respectively;the false positive rates of samples positive with either reagent or samples with gray- zone results were 94. 3% and 100% for reagent A and84. 2% and 88. 9% for reagent B. Conclusion Reagents used for indirect ELISA have high false positive rates and poor specificity and considerable differences exist between homemade indirect reagents. The existing HCV reporting process should be modified. Weakly positive specimens should be further validated by a confirmatory test to protect blood donors' enthusiasm.