Traceability of syphilis antibody detection in preserved samples / 中国输血杂志

ABSTRACT

【Objective】 To investigate whether the current retention methods in blood stations can fully meet the traceability requirements of blood test results by analyzing the traceability of retained samples for syphilis antibody testing. 【Methods】 Thirty-four one-assay-positive deep-well plate retention samples, 68 double-assay-positive deep-well plate retention samples and 263 negative retention blood braids and corresponding deep-well plate retention samples that expired retention period for syphilis antibody testing from 2014 to 2020 in our center were collected. The TP-ELISA assays of two manufacturers were used for retesting, and the results were recorded and compared with the original results statistically. 【Results】 The concordance rate of the double-assay-positive and single-assay-positive samples with their corresponding deep-well plate samples was 98.53%(67/68) and 67.65%(23/34), respectively(P<0.05). Specific results for single-assay-positive syphilis antibody samples and their corresponding deep-well plate retention samples were as follows 1) Single positive (reagent A) 13 out of 14 original samples were 0.65negative results, respectively, 2 retests in 2015 turned negative at 66.67%(2/3), and 1 retest in 2018 and 2020 each turned negative at 50%(1/2). One sample corresponded to a deep-well plate retention sample with a double-assay-positive result after testing. 2) Single positive (Reagent B) 18 out of 20 samples were original samples 0.84accounting for 90%(18/20), of which 6 corresponded to deep-well plate retention samples with negative results, respectively, 71.43%(5/7) of the 5 retests in 2014 and 33.33%(1/3) of the 1 retest in 2015. Four specimens corresponding to the deep well plate retention samples had double-positive-assay results after testing. The concordance rate between the double-positive-assay syphilis antibody specimens and the corresponding deep-well plate retained samples was 100%(52/52) in all years except 93.75%(15/16) in 2014 and four of the deep-well plate retained samples had significantly higher S/CO values. The concordance rate of syphilis antibody-negative samples with their corresponding blood braids and deep-well plate retention specimens was 100%(263/263). 【Conclusion】 Current retention method has significant impact in the traceability of test results for different sample types. The reasons for the differences should be further analyzed, and a more complete and advanced retention method and a more reasonable traceability testing program should be established to meet judicial requirements and reduce costs and consumption.