Prevalence of Gardnerella vaginalis infection and antibiotic resistance pattern of isolates of gynecology clinic patients at Shahriar Noor Hospital from January to June 2020 by PCR and culture methods

Abstract

Background and objectives: Gardnerella vaginalis is one of the most important causes of prevalent genital infections that pose serious risks. This study aimed to determine the prevalence of Gardnerella vaginalis and antibiotic resistance pattern of isolates of patients referred to the gynecology clinic of Shahriar Noor Hospital by PCR and culture methods.

Materials and methods: The study was conducted on 500 patients who had suffered from a vaginal infection. The demographic data of patients were studied. For diagnosis of Gardnerella vaginalis isolates, cultivation in anaerobic conditions, biochemical tests, PCR and Gardnerella vaginalis antibiotic susceptibility test to metronidazole and clindamycin were performed. Data analysis was performed utilizing SPSS statistical software version 19 and the Chi-square test.

Results: Among the 500 patients, 173 were diagnosed with Gardnerella vaginitis. There was a significant relationship between age group, level of education, and contraceptive method with Gardnerella vaginosis incidence. Performing antibiotic susceptibility tests showed that the resistance of Gardnerella vaginalis isolated strains to metronidazole and clindamycin was 86.12% and 17.34%, respectively.

Conclusion: The high prevalence of Gardnerella vaginalis infections confirms the critical role of the bacterium in the occurrence of bacterial vaginosis. Therefore, it is necessary to check the prevalence of bacterial infections to recommend the correct medical treatment in different societies.

Keywords: Antibiotic resistance; Bacterial vaginosis; Gardnerella vaginalis; Polymerase chain reaction; Prevalence.

Fig. 1.

Optical microscope image of Coccobacilli bacteria accumulating around vaginal epithelial cells compared to normal vaginal epithelial cells at 100× magnification

Fig. 2.

Elliptical inhibition zone appears around the strips due to increased antibiotic concentration

Fig. 3.

(A) Agarose gel electrophoresis showing amplification of the 16S-rRNA gene for Gardnerella vaginalis, Lane 1: DNA marker (Ladder 100 bp), Lanes 2–10: DNA samples positive for 16S-rRNA gene, Lane 11: positive control Lane 12: negative control, (B) PCR susceptibility test using sequential dilutions of Gardnerella vaginalis DNA, (C) PCR specificity test, Lane 1: Gardnerella vaginalis DNA, Lane 2: Staphylococcus epidermidis DNA, Lane 3: Escherichia coli DNA, Lane 4: Enterococcus faecalis DNA, Lane 5: Streptococcus agalactiae DNA