Congenital syphilis--who is at risk? A prevalence study at Baragwanath Hospital, Johannesburg, 1985-1986

Abstract

The prevalence of syphilis (or positive serology) in pregnant mothers delivering at Baragwanath Hospital, Johannesburg, was assessed in order to try to establish the prevalence of congenital syphilis and possibly to identify a specific population at risk. From August 1985 to January 1986 all mothers admitted to the major delivery wards were screened to determine whether they were booked or unbooked patients and whether they were seroreactive for syphilis. Infants of seropositive mothers were examined for clinical signs of congenital syphilis. A total of 9,071 patients were screened, 25% unbooked. The prevalence of mothers who had positive serological results with the rapid plasma reagin (RPR) test greater than or equal to 8 U was 1.8% in the booked patients opposed to 9.6% in the unbooked group (P less than 0.00001). During the study period 41 infected infants were found--23 symptomatic, 15 stillborn and 3 aborted fetuses. All these neonates were born to unbooked mothers and had positive RPR test results greater than or equal to 8 U. The results highlight the fact that congenital syphilis is still an important cause of infant morbidity and mortality and that the unbooked mother is at risk of having an affected offspring, especially when her RPR test is seroreactive greater than or equal to 8 U.