New screening approach to detecting congenital syphilis in China: a retrospective cohort study

Abstract

BackgroundDiagnosis of congenital syphilis (CS) is not straightforward and can be challenging. This study aimed to evaluate the validity of an algorithm using timing of maternal antisyphilis treatment and titres of non-treponemal antibody as predictors of CS.MethodsConfirmed CS cases and those where CS was excluded were obtained from the Guangzhou Prevention of Mother-to-Child Transmission of syphilis programme between 2011 and 2019. We calculated sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) using receiver operating characteristics (ROC) in two situations: (1) receiving antisyphilis treatment or no-treatment during pregnancy and (2) initiating treatment before 28 gestational weeks (GWs), initiating after 28 GWs or receiving no treatment for syphilis seropositive women.ResultsAmong 1558 syphilis-exposed children, 39 had confirmed CS. Area under the curve, sensitivity and specificity of maternal non-treponemal titres before treatment and treatment during pregnancy were 0.80, 76.9%, 78.7% and 0.79, 69.2%, 88.7%, respectively, for children with CS. For the algorithm, ROC results showed that PPV and NPV for predicting CS were 37.3% and 96.4% (non-treponemal titres cut-off value 1:8 and no antisyphilis treatment), 9.4% and 100% (non-treponemal titres cut-off value 1:16 and treatment after 28 GWs), 4.2% and 99.5% (non-treponemal titres cut-off value 1:32 and treatment before 28 GWs), respectively.ConclusionsAn algorithm using maternal non-treponemal titres and timing of treatment during pregnancy could be an effective strategy to diagnose or rule out CS, especially when the rate of loss to follow-up is high or there are no straightforward diagnostic tools.

New trends in congenital syphilis: epidemiology, testing in pregnancy, and management

“…A retrospective study in China concluded that maternal nontreponemal titres preceding treatment and timing of treatment in pregnancy can be surrogate indicators in diagnozing congenital syphilis. This study found that nontreponemal titres exceeding 1 : 8 had the highest positive predictive value for congenital syphilis (37.3%) compared with maternal treatment after 28 weeks [53 ▪ ].…”

“…The diagnosis of congenital syphilis can be complex, particularly given the majority of infected infants are asymptomatic at birth. Factors that need to be considered for a diagnosis of congenital syphilis include maternal treatment history, maternal and infant serology, histological and microbiological testing of the placenta, physical examination of the infant and appropriate imaging of the infant [34,48,53 ▪ ] (Table 2). Clinical assessment involves evaluating adequacy of maternal treatment, examination of the newborn (for rash, hepatomegaly, rhinitis, lymphadenopathy), ophthalmology examination, chest and long bone radiographs, neuroimaging and audiology [2,54] (Fig.…”

A Retrospective Cohort Study on Treponema pallidum Infection: Clinical Trends and Treatment Outcomes for Congenital Syphilis in Guangxi, China (2013-2023)

“…This finding is comparable to the national data while very low compared with nearing Asian countries. 11 , 15 As the published report CDC USA showed a random increase of syphilis cases. 16 According to Cohen MS and his co-worker, China was declared a syphilis-free country until the really 1980s, but after the economic reform was introduced, cases now reported in some areas.…”

Associations of toluidine red unheated serum test response to the treatment of syphilis in pregnancy and congenital syphilis: a 10-year real-world study

“…TRUST is used as a type of effective screening strategy in detecting the severity of syphilis [ 13 ] and as an auxiliary surrogate indicator for the diagnosis of congenital syphilis in China. [ 14 ] Serum TRUST titer of the patients before the initial treatment and in the month before delivery, as well as of their newborn babies at birth, were tested routinely and recorded. The diagnosis of congenital syphilis in newborns requires both TPPA and T. pallidum immunoglobulin M test result positive.…”