Establish deferral criterion for HIV serological testing in blood donors

Abstract

Objective To establish deferral criterion of HIV ELISA (enzyme-linked immunosorbent assay) and electrochemiluminescence immunoassay(ECLIA) by using receiver operating characteristic curve(ROC) method to screen HIV reactive blood donors suitable for entering the re-entry process and improve the management efficiency of reactive blood donors. Methods The test results of 92 001 blood donors from February to September 2019 were analyzed, and 177 reactive samples were screened by conventional screening mode (twice ELISA and once nucleic acid), supplemented with electrochemiluminescence immunoassay assay (ECLIA), and confirmed by Western blotting (WB). Screening reactive samples were divided into three groups: group A was both serological and nucleic acid reactivity, group B was only serological reactive, and group C was only nucleic acid reactivity. Its efficacy in blood donor classification was assessed by drawing ROC curves with 99% specific corresponding S/CO low values as the deferral criterion of the corresponding serological method. Results 1) A total of 177 HIV reactive samples were detected in conventional mode, including 34 in group A, 142 in Group B and 1 in Group C. The positive predictive value (PPV) was 100%, 0.75% and 100%, respectively. ECLIA detection mode (once ECLIA and once NAT), a total of 67 HIV reactive samples including 34 in group A, 32 in group B and 1 in group C, with positive predictive values of 100%, 3.7% and 100%, respectively.2) The HIV test results showed diversity, with 36 true positive samples including 1 HIV elite controller and 3 early HIV infections (1 HIV ELISA antigen/antibody window and 2 ELISA HIV antibody window), and 32 serological and NAT cases were reactive infections.3) The deferral limit of ELISA 1 and ELISA 2 in conventional screening mode were 20.25 and 9.85, respectively, can screen 97.14% (34/35) of all true positive samples in group A and B, except for one ELISA HIV antibody window (ELISA 2 reactivity). The positive predictive values were 93.94% and 92.85%, respectively. The ECLIA deferral limit of 7.83 can screens all true positive samples in Groups A and B (35/35)in ECLIA mode. The positive predictive value was 94.59%. Conclusion The establishment of deferral limits in this study can effectively screen HIV-positive blood donors, and the number of screened blood donors is greatly reduced, which is helpful to fine and scientific management of HIV-reactive blood donors. The deferral limit values of different testing reagents are quite different, so each laboratory should choose appropriate testing methods to establish the deferral limit values suitable for the laboratory according to its own testing ability, so as to provide technical support for optimizing the process of returning blood donors to the team.

Keywords

• receiver operating characteristic curve roc
• electrochemiluminescence immunoassay assay eclia
• blood donor deferral
• positive predictive values ppv