Direct Gram's stain of vaginal discharge as a means of diagnosing bacterial vaginosis

Abstract

The diagnosis of bacterial vaginosis (BV) by direct gram-stained smear of vaginal discharge was evaluated in 90 consecutive patients. Vaginal secretions from 20 healthy female volunteers were also examined. All specimens were examined by culture for growth of Gardnerella vaginalis and Lactobacillus spp. Only 35 (38.9%) of the patients with vaginal discharge satisfied the clinical diagnosis of BV. The vaginal gram-stained smear from all these 35 patients contained typical gardnerella morphotypes characteristic of BV and G. vaginalis was isolated from all of them as well as from a further 10 patients who did not satisfy the criteria for diagnosis of BV. The semi-quantitative assessment of gardnerella morphotypes was found to correlate positively with the semi-quantitative assessment of G. vaginalis growth by culture (p less than 0.0001). There was a strong inverse relationship between the quantity of lactobacillus and gardnerella morphotypes. Direct gram-staining of smears should facilitate the diagnosis of BV for clinicians with minimum need for confirmation by culture, particularly in a third world setting with few or no laboratory facilities.