RESUMEN
【Objective】 To analyze the preliminary screening and follow-up testing data of HBV in Yantai area, and discuss the rationality of following up and re-entry program of HBV reactive blood donors. 【Methods】 Donors who were single reagent reactive by enzyme-linked immunosorbent assay (ELISA) in initial screening but non-reactive by nucleic acid testing (NAT) were followed up. Individual NAT(ID-NAT) was performed for HBV DNA, ELISA for HBsAg, HBsAb, HBeAb, HBeAg and HBcAb, and ECLIA for the detection of HBsAg. 【Results】 A total of 547 blood donors were HBsAg ELISA-/NAT+, and 97 were followed up, among which 24 met the requirements of re-entry while 73 did not. Of the 24 blood donors who met the re-entry requirements, 13 donated blood again, with test results all qualified. 【Conclusion】 The combination of ELISA, ID-NAT, and ECLIA methods for following up detection for HBsAg ELISA+ blood donors is recommended. Blood donors with HbsAb S/CO ≥ 10 and negative results for other tests met the re-entry requirements, with a re-entry rate at 24.74%, and the re-donation qualified rate of blood donors after re-entry was 100%.
RESUMEN
【Objective】 To retrospectively analyze the detection results of blood donors with HBsAg reactivity to single reagent detected by enzyme-linked immunosorbent assay (ELISA) in our center, so as to provide basis for further consolidating the blood donor team. 【Methods】 Samples of blood donors who had been deferred for at least 6 months due to HBsAg reactivity to sole ELISA assay were collected, and HBsAg ELISA and NAT were further performed. Meanwhile, HBsAg/HBsAb/HBeAg/HBeAb/HBcAb were detected by Roche electrochemiluminescence immunoassay, and the results were statistically analyzed. 【Results】 Among these 51 selected samples, 45 were negative to two assays, 6 were reactive to sole assay, with reactivity-yield rate at 11.76% (6/51). The results of NAT/ECLIA were all negative. For five indicators of hepatitis B virus infection, 23 samples were all negative and 28 were partially positive, mainly anti-HBs, anti-HBc and anti-HBe. 【Conclusion】 The follow-up detection of HBsAg ELISA sole-reagent reactive samples, supplemented with the detection of HBV serological markers, can reduce the number of deferred blood donors, increase the willingness to donate blood again, and protect the rights and interests of blood donors.
RESUMEN
【Objective】 To perform electrochemiluminescence immunoassay (ECLIA) and Western blotting (WB) confirmation tests for HIV reactive samples in blood screening, and analyze the correlation between ELISA (enzyme-linked immunosorbent assay), ECLIA results and confirmed infection, so as to provide data support for the application of ECLIA in blood screening. 【Methods】 177 HIV reactive samples in blood screening testing detected by our laboratory from February to October 2019 were collected, of which 137 were reactiv to isolated ELISA reagent e, 39 to dual ELISA reagent, and 1 in window period. Ten maker-negative samples were randomly selected to undergo ECLIA with the above 177 samples. HIV reactive samples were sent to Centers for Disease Control and Prevention (CDC) for confirmation tests, and the results were analyzed and compared. 【Results】 Among the 177 HIV reactive samples, 66 were ECLIA reactive, 111 negative, and the 10 maker-negative samples remained negative. The sensitivity, specificity, positive predictive value, negative predictive value and total concordance rate of ECLIA were 97.1%, 81.1%, 55%, 99.1% and 84.2%, respectively, showing better performance than that of two ELISA reagents(P0.05). The positive predictive value and specificity were tested by chi-square test, and the difference between ECLIA and reagent 2 was statistically significant (P<0.05). The ECLIA results showed significant correlation with the confirmation results with good consistency(examed by Kappa test). Among the three reagents, ECLIA presented highest accuracy and largest Youden index. 【Conclusion】 ECLIA presents high detection sensitivity, which can improve the detection ability of early HIV infection and shorten the window period of HIV detection, therefore should be popularized in blood screening.
RESUMEN
【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.
RESUMEN
【Objective】 To evaluate the performance of electrochemiluminescence immunoassay (ECLIA) in detecting HIV antigen/antibody in blood screening. 【Methods】 A total of 128 donors, reactive to anti-HIV(ELISA)testing, from September 2016 to September 2020 were enrolled, and seven samples were reactive to double anti-HIV reagents, among which 6 were confirmed by WB, 1 confirmed by NAT as negative.Two group of donors, reactive to solo anti-HIV reagent but being confirmed negative by WB(n=121) vs.randomly selected donors non-reactive to ELISA + NAT(June to September 2020, n=1360), were subjected to HIV antigen/antibody testing using ECLIA to compare the testing results, including concordance rate, sensitivity and specificity. 【Results】 The ECLIA results remained non-reactive for 1360 samples initially non-reactive to both ELISA and NAT.The concordance rate of anti-HIV reactivity by ECLIA and ELISA+ WB were 100%(6/6). For 122 samples, reactive to ELISA anti-HIV testing but nonreactive to confirmatory testing, 4(3.28%)of them were reactive to HIV antigen/antibody testing and 118(96.72%) nonreactive, with the concordance rate of ECLIA and ELISA at 96.88%(124/128). The sensitivity, specificity and false positive rate of ECLIA and ELISA were 100% vs 100%, 99.73% vs 91.77%, and 0.27% vs 8.23%, respectively. 【Conclusion】 ECLIA for HIV antigen/antibody detection has good sensitivity and specificity, which can meet the requirements of blood screening, and the false positive rate is lower than that of ELISA, adopted commonly in blood bank at present.
RESUMEN
【Objective】 To investigate NAT non-reactive results implicated in HBsAg ELISA reactive voluntary blood donors in Shenzhen. 【Methods】 HBsAg ELISA+ but NAT-blood samples were collected, and HBsAg was further retested by TRFIA, Roche ECLIA and neutralization test. HBV DNA of individual donation was detected by commercial Roche MPX and Uultrio Elite, and virus nucleic acid was extracted via 2.5 mL. Molecular characterizations of HBsAg+ /NAT-samples were determined by quantitative polymerase chain reaction(qPCR) and nested PCR amplifification of the precore and core promoter regions and HBsAg(S) region. HBV serological markers were detected, and the samples with suspicious results were followed up and detected by multi-assay. 【Results】 Among 67 602 samples, 73(0.11%) HBsAg ELISA+ and NAT-blood samples were enrolled in the study. 15(20.5%, 15/73) were confirmed HBsAg+ by TRFIA, ECLI and five alternative DNA assays, and the other 2(2.7%, 2/73) were further identified as HBsAg+ by follow-up study. In 17 confirmed HBsAg+ samples, the viral loads ranged undetectable to 378 IU/mL, with the median of 10.1 IU/mL. Weak correlation was found between HBsAg and HBV DNA load(R2=0.394 4). 【Conclusion】 Some Hepatitis B virus infected blood samples may miss even with different HBsAg assays. Multi-assays with high sensitivity should be combined for blood screening to ensure blood safety..The inconsistent results should be followed up and further tested for hepatitis B serological markers to assist the confirmation.