Field efficiency of syphilis screening in antenatal care lessons from Gutu District in Zimbabwe

Objectives'. To determine coverage for antenatal syphilis screening in a rural area and evaluate the accuracy of on-site Rapid Plasma Reagin (RPR) tests performed by nurse-midwives. Design: Descriptive cross sectional. Setting'. Rural Health Centres (n=23) in the Gutu District of Zimbabwe. Subjects: Women booking for antenatal care in the district were used to determine coverage of screening. Results from women who had an RPR test performed during a nine week period were used in assessing the accuracy of tests performed by nurse-midwives. Intervention: On-site antenatal screening for syphilis using an RPR kit with immediate results and treatment for women who tested positive. Main Outcome Measures: Prevalence of syphilis (positive RPR) at booking and the level of agreement between three observers (RHC nurse-midwife, medical practitioner under field conditions and medical laboratory technologist). Results: Eighty five percent of women were screened for syphilis at the first antenatal visit and 11% had a positive RPR. Almost all (97.3%) women with a positive RPR test result were treated. The accuracy of tests performed by RHC staff was poor with a sensitivity of 40% (95% Cl 21.8 to 61.1) when compared to those done by the medical practitioner and 8.7% (95% Cl 1.5 to 29.5) when compared to those done in a laboratory. The predictive value of a positive test was 22.7% and that of a negative test was 94.9%. Conclusion: The coverage of screening for syphilis in pregnant women in Gutu District was good but the results were unreliable. There is need for nurse-midwives, who perform the majority of RPR tests in the RHC, to receive adequate training to ensure competence in testing and to strengthen quality control procedures.