ABSTRACT
【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.
ABSTRACT
【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.
ABSTRACT
【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.