The Performance Of CMIA For Serum Specimens With HBsAg Weak Reaction

Background:Hepatitis B surface antigen(HBsAg)is one of the most widely used serological markers in clinical work,and it is also the core indicator recommended by the World Health Organization for the diagnosis of HBV infection.At present,the main detection methods of HBsAg are chemiluminescence immunoassay(CLIA)and enzyme-linked immunosorbent assay(ELISA).Chemiluminescent microparticle immunoassay(CMIA)is a kind of CLIA.CLIA has become more and more popular in clinic because of its advantages including flexible detection,high degree of automation and easier to realize the standardization of testing process.In recent years,some studies have compared the performance of CLIA and ELISA in the detection of HBV serological markers,but few studies have explored the reliability of the results with weak reaction to HBsAg detected by CLIA and ELISA.Objective:The purpose of this study is to evaluate the performance of CMIA for serum specimens with weak reaction to HBsAg.Method:Retrieving data from the First Affiliated Hospital of Nanchang University,the positive rate of CMIA and ELISA in the detection of HBsAg in serum of outpatients were analyzed.They were used to understand the sensitivity difference between the two methods.On this basis,serum specimens with weak reaction to HBsAg detected by CMIA and ELISA in clinical routine test were collected and tested by ELISA and CMIA in parallel to evaluate the difference of results between CMIA and ELISA.At the same time,all the serum specimens with weak reaction to HBsAg were confirmed by neutralization confirmation test to evaluate the reliability of the weak reactive results detected by CMIA.On the basis of confirming the reliability of the test results,serum specimens with weak reaction to HBsAg were selected to evaluatethe precision of CMIA in detecting weak reactive serum specimens according to EP-15A2 document.Result:1.The results of detection of HBsAg in 55737 clinical patients from July 2018 to October 2018 were included in this study.The results showed that the positive rate of HBsAg in CMIA was significantly higher than that in ELISA(21.00% vs 18.41%,P = 0.032).2.183 serum specimens with weak reaction to HBsAg(0.05-0.5IU/ml)detected by CMIA were included in this study.The results showed that only 88(48.09%)of them were positive by ELISA.The results of 183 serum specimens confirmed by specific antibody neutralization test as gold standard showed that 168 of them were HBsAg positive.The statistical results showed that the positive predictive value of CMIA was 91.80%;and the sensitivity of ELISA was 52.38%,but the positive predictive value was 100%.3.In this study,50 serum specimens with weak reaction to HBsAg(S/CO: 1-4)detected by ELISA were included,and these specimens were detected in parallel by CMIA detection system.The results of CMIA showed that 47 of them were reactive specimens.The results were negative in 3 cases with different results.4.The results of segmented analysis for all the specimens with HBsAg weak reaction detected by CMIA showed that 100% of the specimens with CMIA detection value ? 0.16 IU / ml were positive in neutralization confirmation test.5.The results of precision test showed that the coefficient of variation of repeatability and the coefficient of variation of intermediate precision of CMIA were5.06% and 5.56%,respectively.Conclusion:Compared with the traditional ELISA technology,CMIA has not only higher sensitivity,but also good reliability and precision.For specimens with CMIA test value ? 0.16 IU / ml,100% of neutralization confirmation test is positive.