Follow-up study on the serological reactivity of infants diagnosed with congenital syphilis in Shanghai / 中华传染病杂志

ABSTRACT

Objective To determine the status of false-positive report of congenital syphilis (CS),to analyze the possible causes of mis-diagnosis.Methods Basic information on CS in Shanghai in the past five years was collected.We identified infants diagnosed with CS and followed up the sero- logical reactivity of those patients and their mothers.The serological reactivity[rapid plasmin reagin (RPR)and treponema palidum hemagglutination assay(TPPA)]of infants was followed-up for up to 24 months,or until both antibodies turned to negative.The medical history of the mothers was col- lected,and their sera were examined for syphilitic antibodies.Results Total 99 infants diagnosed with CS were recruited. The major diagnostic method was treponemal antibody detection.Only 31.3% of the 99 infants exhibited clinical symptoms or syphilis-like symptoms at delivery.The cumu- lative RPR loss rates of the infants were 44.2%,64.0%,72.7%,83.9% and 87.1% at 1-3,3-6,6- 12,12-18 and 18-24 months after birth,respectively.The cumulative TPPA loss rates were 1.1%, 18.6%,44.6%,66.7% and 74.4% for 1-3,3-6,6-12,12-18 and 18-24 months after birth,respec- tively.TPPA remained positive in all mothers with syphilis.Conclusion The diagnosis of congenital syphilis determined solely by the positive tests of RPR and TPPA is unreliable and can be misdiagno- sis.The diagnosis and management of congenital syphilis should be urgently improved,and that the profes- sional health institutions should perform and closely monitor the quality controls in the diagnosis of CS and standardize the intervention strategy of maternal syphilis.