Syphilis in pregnant women in Zambia

Abstract

Because of the high incidence of congenital syphilis at the University Teaching Hospital, Lusaka, Zambia, the potential risks of congenital infection and fetal loss due to syphilis were assessed by screening 202 antenatal patients, 340 pregnant women admitted to the hospital whose pregnancies ended in either spontaneous abortion or stillbirth, and 469 consecutive babies delivered at the hospital. Primary serological screening was performed with the rapid plasma reagin test, and reactive sera were confirmed by the Treponema pallidum haemagglutination test. In all cases detailed histories were obtained and patients were examined for clinical signs of syphilis. The TPHA test result was reactive in 12.5% of antenatal patients and in 42% of women who aborted in the later half of pregnancy. Among 469 consecutive babies delivered at the hospital, 30 had reactive results to the TPHA test; of these two were stillborn and four had signs of congenital syphilis at birth. Thus, syphilis appears to affect adversely an appreciably high number of pregnant women in Zambia. For this reason a special campaign to screen adequately and treat pregnant women and neonates is needed.

PIP: Three groups of patients were investigated: 202 pregnant women who attended a suburban antenatal clinic for the first time; 340 pregnant women whose pregnancies resulted in either spontaneous abortion or stillbirth; and 464 pregnant women admitted to the labor ward of the University Teaching Hospital, Lusaka. The socioeconomic background and relevant obstetric and prenatal histories of each patient were recorded; the patients were examined for clinical signs of syphilis. Blood samples were obtained for preliminary serological screening for treponemal antibodies with the rapid plasma reagin (RPR) test and reactive sera were tested by the Treponema pallidum hemagglutination (TPHA) test. The cerebrospinal fluid was examined routinely for the presence of treponemal antibodies. 85% of the women in the antenatal group were 20 or more weeks pregnant. 173 of the 240 spontaneous abortions occurred before the 20th weeks of pregnancy. Seroreactivity in the TPHA test in these two subgroups was 9.8% and 41.8% respectively, In 36 of the 42 seroreactive women who gave birth to stillborn babies, the presence of syphilis was the only recognizable etiological factor. 35 women had premature deliveries; 40 of the babies were macerated at birth. In the 167 cases of fetal loss beyond the 20th week of pregnancy, there were no significant differences in age, marital and economic status, education, and parity between seropositive and seronegative groups. A history of previous abortion or stillbirth and antenatal reactivity to the Venereal Disease Research Laboratory test was significant in the seroreactive group. Among the 30 seroreactive babies, 4 had clinical signs of congenital syphilis at birth (detected by darkfield microscopy of exudate in 3 babies), 2 were stillborn, and 8 more required intensive care because of prematurity, asphyxia, and conjunctivitis. The overall mortality and morbidity rates in babies whose sera were reactive in the TPHA test were significantly higher (p 0.001) than in those whose sera were not reactive.