Confirmation and re-examination of reactive anti-TP screening in blood donors
10.13303/j.cjbt.issn.1004-549x.2026.07.017
- VernacularTitle:献血者抗-TP筛查反应性确认与复查研究
- Author:
Qin YU
1
;
Tingting XU
1
;
Bangrui CHEN
1
;
Lei ZHAO
1
Author Information
1. Wuhan Blood Center, Wuhan 430030, China
- Publication Type:Journal Article
- Keywords:
blood donor;
treponema pallidum(TP);
enzyme-linked immunosorbnent assay (ELISA);
Western blotting;
treponema pallidumparticle agglutination (TPPA);
donor re-examination
- From:
Chinese Journal of Blood Transfusion
2026;39(7):928-933
- CountryChina
- Language:Chinese
-
Abstract:
Objective: To confirm the reactive anti-TP ELISA screening results in blood donor samples, and analyze implementaion of re-examination among reactive donors, so as to provide data support for effectively formulating re-examination strategies. Methods: Confirmation tests were performed on 331 samples (including 224 cases with dual-reagent reactivity and 107 cases with single-reagent reactivity) using treponema pallidum particle agglutination assays (TPPA). A total of 136 blood samples were collected from blood donors who have previously tested for anti-TP ELISA with single-reagent reactivity and voluntarily applied for re-examination from 2020 to 2024. Infectious disease indicators were detected in accordance with the "Technical Operating Procedures of Blood Stations (2019 Edition)". Among them, anti-TP screening was performed using ELISA reagents from two different manufacturers, and HBV/HCV/HIV nucleic acid testing was conducted using an individual donation nucleic acid testing (ID-NAT) mode. Supplementary tests (WB or TPPA) were conducted on samples with anti-TP ELISA single-reagent reactivity. A two-sided Pearson's chi-squared test or Fisher's exact test was used to evaluate the differences of the positive rates of anti-TP among different groups or reagents. Results: Among the 331 samples, the confirmed positive rate was 93.75% (210/224) for dual-reagent reactive samples, and 2.8% (3/107) for single-reagent reactive samples. The confirmed positive rates of double reagent reactive samples with different reagent combinations were 91.7% (95% CI: 85.6%-95.5%), 95.6% (95% CI: 85.2%-98.8%), 96.6% (95% CI: 86.2%-97.3%) respectively, with no statistically significant difference (χ
=1.597, P=0.463). From 2020 to 2024, 994 donors showed anti-TP ELISA single-reagent reactive results. Among them, 136 (136/994, 13.68%) donors voluntarily applied for re-examination. After the first round of re-examination, 88 (88/136, 64.71%) donors passed the re-examination, and 18 donors were permanently deffered (18/136, 13.24%). Among the permanently quarantined donors, 12 donors remained anti-TP ELISA single-reagent reactive, including 8 confirmed positive for TP-specific antobodies and 4 with indeterminate results. The remaining 6 donors converted to dual-reagent reactive. Conclusion: The dual-reagent reactive results in anti-TP ELISA has a high true positive rate, and the corresponding blood donors can be directly deffered. The majority of single-reagent reactive anti TP-ELISA results are false positives. Timely confirmation or supplementary testing allows prompt notification of evaluation results to blood donors, and reduces unnecessary follow-up examinations. This helps improve the quality of blood donor services and management efficiency, as well as prevent blood donor attrition.
