Comparison of PAP, Modified Pap and Gram Stained Cervico-Vaginal Smears in the Diagnosis of Bacterial Vaginosis in Women Attending Thika District Hospital

Abstract

Objective: To compare Pap, Modified Pap and Gram stained cervico-vaginal smears in the diagnosis of bacterial vaginosis in women to establish if Modified Pap was a suitable alternative to Pap method. Design: Descriptive cross-sectional survey of bacterial vaginosis with a comparative evaluation of three methods. Setting: Thika District Level Five (County) Hospital. Subjects: A total of 150 female patients who consulted for services at Antenatal Care and Family Planning clinics at Thika district Level 5 (County) hospital between November 2016 and May 2017and who met the inclusion criteria were recruited into the study. Main outcome measures: Presence or absence of bacterial vaginosis. Results: The study showed that Pap and Modified Pap methods yielded sensitivity of 47.6% and 26.2%, positive predictive value (PPV) of 80.0% and 68.8%, negative predictive value (NPV) of 82.4% and 76.9%, likelihood ratio of positive result (LR+) of 10.3 and 5.69, likelihood ratio of negative result (LR-) of 0.55 and 0.77 respectively and specificity of 95.4% and overall diagnostic accuracy of 38.9% for both methods. Conclusion: The Modified Pap staining method has diagnostic value when it is positive in diagnosis of bacterial vaginosis and can therefore be a suitable alternative to Pap method as a confirmatory test for bacterial vaginosis.