Effect of metronidazole on the growth of vaginal lactobacilli in female athletes

ABSTRACT

Lactobacillus strains isolated from female athletes were tested. MRS broth was supplemented with a range of Metronidazole concentrations from 128 to 2000 μg/ml. The growth of these strains was monitored by measuring optical density at 3-hour intervals over 24 hours. Results: It was observed that at Metronidazole concentrations up to 128 μg/ml, there was no significant impact on the growth of the Lactobacillus strains. However, at concentrations above 512 μg/ml, Metronidazole significantly inhibited their growth. The response to Metronidazole varied among different Lactobacillus strains. For instance, at a concentration of 256 μg/ml, Lactobacillus delbrueckii, Lactobacillus jensenii, and Lactobacillus vaginalis showed notable inhibition, whereas Lactobacillus crispatus, Lactobacillus gasseri, and Lactobacillus fermentum were not significantly affected. Discussion: High concentrations of Metronidazole were found to inhibit the growth of the six Lactobacillus strains isolated from female athletes. Lower concentrations had negligible effects. The differential response of Lactobacillus strains to varying concentrations of Metronidazole (between 128 μg/ml and 512 μg/ml) highlights the need for careful consideration of Metronidazole use in managing vaginal microbiota health in female athletes (AU)