Clinical diagnosis of bacterial vaginosis

Bacterial vaginosis (often called nonspecific vaginitis or gardnerella vaginitis) is an incompletely understood disease whose initial diagnosis is often one of exclusion made when no trichomonads, yeast, or evidence of cervicitis is found during the initial examination of a woman complaining of a vaginal discharge. To increase the accuracy of the initial diagnosis, specific criteria were used before the clinical diagnosis of bacterial vaginosis was made. The presence of three of the following four criteria was necessary: 1) vaginal pH greater than 4.5; 2) clue cells on the saline wet mount; 3) thin, homogeneous-appearing discharge; or 4) positive potassium hydroxide "whiff test." A study on 100 consecutive women presenting to the emergency department with vaginal symptoms was done. Of those women meeting the criteria, 93% (54/58) obtained relief of their symptoms by treatment with metronidazole. Of those women not meeting the criteria, only 24% (10/42) were cured (P less than .001). The sensitivity, specificity, and total error rates of these criteria were 84, 89, and 14%, respectively.