Assessment of infection status in treponema pallidum antibody-reactive blood donors / 中国输血杂志

ABSTRACT

【Objective】 To evaluate the infection status and potential infectivity of Treponema pallidum specific antibody (anti-TP) reactive blood donors, and to provide reference for the key prevention and screening of TP under the current screening strategy. 【Methods】 From February to October 2021, 133 blood donors were tested reactive by two different anti-TP ELISA kits (77 cases were dual-reagent reactive and 56 cases were single-reagent reactive). Syphilis specific IgM antibody (TP-IgM) and IgG antibody (TP-IgG) were detected by Western blot (WB), and TRUST was conducted. The results were analyzed. 【Results】 Of the 133 samples, 24 (18.05%) were positive for TP-IgM, 40 (30.07%) were positive for TP-IgG, and 3 (2.26%) were positive for TRUST. Among them, 12 cases (15.58%) were TP-IgM positive and 40 cases (51.95%) were TP-IgG positive in 77 cases of double reagent reactivity, and 12 cases (21.43%) were TP-IgM positive and 0 was TP-IgG positive in 56 cases of single reagent reactivity. There was no significant difference in the positive rate of TP-IgM between the two groups (P>0.05), while the positive rate of TP-IgG in donors with double reagent reaction was higher than that in donors with single reagent reaction (P<0.05). In addition, among the 133 anti-TP-reactive blood donors, 15 cases were positive for single TP-IgM (11.28%, accounting for 62.50% of the total positive number of TP-IgM, a total of 12 cases of TP-IgM positive among the single reagent reactive patients, and all of them were TP-IgM positive and TP-IgG negative); 30 cases were positive for single TP-IgG (22.56%, accounting for 75.00% of the total positive number of TP-IgG). There were 55 cases (41.35%) who were negative for TP-IgM and TP-IgG, and 8 cases (6.02%) were both positive. 【Conclusion】 The TP-IgM positive donors in anti-TP reactive blood donors are infectious, but the positive rate is not high. Those with single reagent reactivity and single TP-IgM positive are prone to miss detection, which should be controlled. Those who were both TP-IgM and TP-IgG negative and those who were only TP-IgG positive may be false reactivity and the phenomenon of lifelong antibody expression. It is suggested to consider adding TP-IgM detection as a measurement index for permanent deferral of both reagents.