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% CI 21.8 to 61.1) when compared to those done by the medical practitioner and 8.7% (95% CI 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.