Diagnosis of bacterial vaginosis by direct gram stain of vaginal fluid

Abstract

To determine whether bacterial vaginosis (BV), also known as nonspecific vaginitis, could be diagnosed by evaluating a Gram stain of vaginal fluid, we examined samples from 60 women of whom 25 had clinical evidence of BV and 35 had candidal vaginitis or normal examinations. An inverse relationship between the quantity of the Lactobacillus morphotype (large gram-positive rods) and of the Gardnerella morphotype (small gram-variable rods) was noted on Gram stain (P < 0.001). When Gram stain showed a predominance (3 to 4+) of the Lactobacillus morphotype with or without the Gardnerella morphotype, it was interpreted as normal. When Gram stain showed mixed flora consisting of gram-positive, gramnegative, or gram-variable bacteria and the Lactobacillus morphotype was decreased or absent (0 to 2+), the Gram stain was interpreted as consistent with BV. Gram stain was consistent with BV in 25 of 25 women given a clinical diagnosis of BV and in none of 35 women with candidal vaginitis or normal examinations. Duplicate slides prepared from 20 additional specimens of vaginal fluid were stained by two methods and examined by three evaluators. Interevaluator interpretations and intraevaluator interpretations of duplicate slides were in agreement with one another and with the clinical diagnosis .90% of the time. We concluded that a microscopically detectable change in vaginal microflora from the Lactobacillus morphotype, with or without the Gardnerella morphotype (normal), to a mixed flora with few or no Lactobacillus morphotypes (BV) can be used in the diagnosis of BV.

Diagnosis of Bacterial Vaginosis in a Gynaecology Clinic

“…It was 100% specific and sensitive in comparison with the compound criteria for the diagnosis of bacterial vaginosis. Spiegel et al (1983) were of the same opinion based on observations on 25 women with bacterial vaginosis in a study group of 60. However, in a larger study of bacterial vaginosis in pregnant women (Krohn et al 1989), the Gram stain was reported to have a specificity of 95% but a sensitivity of only 62%.…”

“…The microscopist (P.E.H.) was unaware of the other results and used the criteria of Spiegel et al (1983) to diagnose bacterial vaginosis. In this method the numbers of organisms per high power field (X 1000) are graded as: 1+, <1 per field; 2+, 1-5 per field; 3+, 5-30 per field; 4+, >30 per field.…”

Evaluation and management of vaginitis

“…The diagnosis requires the presence of fewer than five Lactobacillus morphotypes, five or more Gardnerella morphotypes, and five or more other morphotypes (gram-positive cocci, small gram-negative rods, curved gram-variable rods, or fusiforms) per high-power field. 88 The Vaginal Infection and Prematurity Study Group developed a more widely utilized method to diagnose bacterial vaginosis using the gram stain, the Nugent system. 5 A scoring system from 0 to 10 grades the severity of bacterial vaginosis using the most reliable bacterial morphotypes to create a summary score of the alteration in vaginal flora.…”

The effect of “breathable” panty liners on the female lower genital tract

“…The microbiology examination identified 3 types of vaginal flora: type 1 (a dominance of Gram-positive bacilli); type 2 (a balance between lactobacilli and other bacteria); and type 3 (the absence of lactobacilli) [13]. Vaginal candidiasis was diagnosed based on the presence of fungi (pseudohyphae and spores) on a vaginal smear or following culture.…”

“…Despite the high prevalence of panty liner use, few studies have assessed the effect on the vaginal ecosystem of frequent use for lengthy periods [5,13]. Furthermore, the few studies that have been carried out have analyzed the genital microflora of women who used panty liners with vapor-impermeable, rather than vapor-permeable, back sheets.…”