RESUMO
【Objective】 To analyze the influencing factors of the repeat reactive (RR) rates of minipools implicated in minipool (MP) nucleic acid testing(NAT) in Xiamen Blood Center, in order to provide reference for NAT. 【Methods】 Samples of blood donors from January 1, 2019 to October 31, 2022 were collected in Xiamen Blood Center and tested by MP-NAT(pools of six). Statistical analysis and comparison of MP-NAT RR rates was performed among different years, testers, reagent batches, instrument combinations, CT values of MP-NAT reactive pools and sample backgrounds. 【Results】 A total of 234 715 blood samples were tested by MP-NAT, and 428 pools were reactive, in which 248 pools were individual-donor NAT reactive, with a MP-NAT RR rate of 57.9%. The difference of MP-NAT RR rates were not statistically significant among different years, testers, reagent batches, instrument combinations, and sample backgrounds (P> 0.05). The difference of MP-NAT RR rates among different CT values of MP-NAT reactive pools was statistically significant (χ2=69.587, P<0.05). Significantly abnormal RR rate accurred in two months in 2022, and returned to normal after timely handling. 【Conclusion】 The MP-NAT RR rates is one of the important indicators to monitor the quality of NAT. Once there is a significant change in the MP-NAT RR rates, comprehensive analysis and timely handling should be carried out to ensure the quality of blood detection.
RESUMO
【Objective】 To compare the results by minipool and individual NAT on blood samples with HBsAg detection S/CO value between 0.25-0.90 by ELISA, in order to re-evaluate the safety of NAT for such negative samples with high HBsAg S/CO value and provide references for the optimization of detection process. 【Methods】 A total of 30 blood samples which were non-reactive for HBsAg by ELISA twice and with the S/CO value of any reagent between 0.25-0.90 (defined as " high S/CO value negative" ) from our center from February to October 2020 were collected, and minipool test of 6 samples and individual test were performed in parallel. 11 samples which were negative by minipool tests but positive by individual test were submitted to repeated NAT minipool tests, and the results of each test were recorded and analyzed. 【Results】 The median S/CO values of the 30 samples by two ELISA reagents were 0.565 and 0.320, respectively, and the differences were statistically significant (P 0.05). 【Conclusion】 The NAT-yield of samples with high ELISA HBsAg S/CO value was high in individual test and low in minipool test, and the NAT-yield in minipool test could be improved by repetitive test. Therefore, the safety of NAT for samples with high HBsAg S/CO value should be re-evaluated as minipool test is dominant in blood stations. Individual NAT test is recommended for such samples currently as there is no any other more sensitive detection approaches.