CORRELATION BETWEEN CERVICAL CYTOLOGIC RESULTS AND GRAM STAIN AS DIAGNOSTIC-TESTS FOR BACTERIAL VAGINOSIS

OBJECTIVE: Our purpose was to determine the reliability of the Papanic olaou smear in making the diagnosis of bacterial vaginosis with the va ginal Gram stain used as the diagnostic standard. STUDY DESIGN: We con ducted a prospective, blinded, cross-sectional study of 210 consecutiv e patients referred to the Colposcopy Clinic for evaluation of abnorma l cervical cytologic results, Each patient had a standard Papanicolaou smear and Gram stain of vaginal discharge. The sensitivity, specifici ty, positive predictive value, and negative predictive value of the Pa panicolaou smear were determined with the Gram stain used as the stand ard for diagnosis of bacterial vaginosis. RESULTS: Of the 210 patients , 80 (38.14b) had Gram stains that were positive for bacterial vaginos is and 118 (56.2%) had negative Gram stains. Twelve (5.7%) had interme diate Gram stains that were also considered negative. Of the 80 patien ts with positive Gram stains, 44 had cervical smears consistent with b acterial vaginosis and 36 had negative smears. Of the 130 patients wit h negative Gram stains, two had a positive cervical smear. Therefore, compared to the Gram stain, cervical cytologic test results had a sens itivity of 55% and a specificity of 98%. The respective positive predi ctive and negative predictive values were 96% and 78%. CONCLUSION: Com pared to Gram stain of vaginal secretions, the cervical Papanicolaou s mear has fair sensitivity (55%) and excellent positive predictive valu e (96%) in diagnosing bacterial vaginosis.