Uncertain factors of detecting Treponema pallidum antibody by enzyme linked immunosorbent assay

Objective To study the uncertain factors of the false positive results of Treponema pallidum specific antibody( antiTP) detected by enzyme linked immunosorbent assay( ELISA). Methods Anti-TP was detected in 2619 samples by ELISA. The positive samples were examined again by tolulized red unheated serum test( TRUST) and T. pallidum particle assay( TPPA). Results The S /CO 1. 0 in 231 positive samples detected by ELISA were 201,The 201 positive samples were examined again by TRUST and confirmed positive by TPPA. The positive samples by TRUST were 169,and by TPPA were 196. The coincidence rate of ELISA and TPPA was 97. 5%. In 30 samples' S /CO between 0. 7 and 1. 0,the positive samples examined again by TRUST were 12,and confirmed positive by TPPA were 19. The coincidence rate of ELISA and TPPA was 63. 3%. Conclusions The method of ELISA is affected by the uncertain factors,So false positive results exist. The sample's S /CO between 0. 7 and 1. 0 should be examined by TRUST and TPPA jointly.