Anaerobic Bacteria in Nonspecific Vaginitis

TLDR

The study aimed to investigate the etiology of nonspecific vaginitis by analyzing vaginal fluid from normal women and 53 affected women. The authors used quantitative anaerobic cultures and gas‑liquid chromatography to measure short‑chain organic‑acid metabolites of the vaginal flora. Normal vaginal fluid had lactate as the predominant acid produced by lactobacillus and streptococcus, whereas nonspecific vaginitis showed decreased lactate and increased succinate, acetate, butyrate, and propionate with Gardnerella vaginalis and other anaerobes; metronidazole treatment restored lactate dominance and eliminated butyrate and propionate, supporting that certain anaerobes with G.

Abstract

To study the cause of nonspecific vaginitis, we analyzed vaginal fluid from normal women and from 53 women with nonspecific vaginitis, using quantitative anaerobic cultures and gas-liquid chromatography for short-chained organic-acid metabolites of the microbial flora. In normal vaginal fluid, lactate was the predominant acid, and the predominant organisms were lactobacillus and streptococcus species (lactate producers). In nonspecific vaginitis, lactate was decreased, whereas succinate, acetate, butyrate, and propionate were increased, the predominant flora included Gardnerella (Haemophilus) vaginalis (acetate producer), and anaerobes, which included bacteroides species (succinate producers) and peptococcus species (butyrate and acetate producers). After metronidazole therapy, symptoms and signs of nonspecific vaginitis cleared, butyrate and propionate disappeared, and lactate and lactate-producing organisms became predominant. We conclude that certain anaerobes act with G. vaginalis as causes of nonspecific vaginitis, and that a high ratio of succinate to lactate in vaginal fluid is a useful indicator in the diagnosis of this condition.