[Accuracy analysis and comparison of different serological detection methods in syphilis]

Objective: To compare the accuracy of different methods by reviewing syphilis serologic screening external quality assessment (EQA) data of Chinese primary health care institutions. Methods: The EQA was based on one or two distinct shipments from 2011 to 2016. Each shipment consisted of five serum samples. The laboratories performed the EQA and sent back the results by the deadline. The results were analyzed using the standard procedures and methods. Results: Six different methods were used for syphilis serologic screening: enzyme linked immunosorbent assay, colloidal gold method, Treponema pallidum particle agglutination (TPPA) test, rapid plasma reagin card test, toluidine red unheated serum reagin test and chemiluminescence immunoassay. From 2011 to 2016, the qualified rate of the colloidal gold method and TPPA had improved from 67.78% to 98.89% and 27.27% to 100%, respectively. The positive coincidence rate of TPPA had changed from 54.55% to 100%. The negative coincidence rate of TRUST had changed from 78.95% to 100%. Conclusions: There were differences between different methods of syphilis serological detection. With the implementation of the EQA performance, the qualified rate, positive coincidence rate, and negative coincidence rate were improved in the primary maternal and child health care institutions.