[Maternal and congenital syphilis in two Mexican hospitals: evaluation of a rapid diagnostic test]

To estimate the prevalence of maternal and neonatal syphilis, to assess the usefulness of a rapid treponemic diagnostic test, and to evaluate the frequency of screening for syphilis during prenatal care in Mexican women.

This was a cross-sectional study that included 1,322 women interviewed in two hospitals (Hospital General in Cuernavaca, Morelos, and Hospital de la Mujer in Mexico City). Women answered a questionnaire on reproductive background, exposure to sexually transmitted infections and prenatal care. In order to diagnose syphilis, a rapid Determine TP test and a latex-VDRL test were used among all participating women. Positive cases were confirmed using FTA-ABS test.

Prevalence of serologically active syphilis was 0.3% (4/1322). Using as comparison standard a combination of VDRL and FTA-ABS tests, the Determine TP test had a sensitivity and specificity of 100%. Two newborns with positive FTA-ABS IgM, one negative with FTA-ABS IgM and one first-trimester abortion were found from seropositive women. Prenatal serum screening for syphilis was conducted in only 6.9% of women included in the study.

Although the prevalence of maternal syphilis is relatively low, results show that if the situation found in the hospitals studied is shared by other hospitals in Mexico, a systematic screening for maternal syphilis would help to diagnose more cases of this infection than the number reported in official figures. Screening of syphilis in pregnant women using rapid tests may help in the prevention of congenital syphilis.