Identification of Gardnerella vaginalis by Molecular Methods in Women Diagnosed With Bacterial Vaginosis in Isfahan, Iran

Bacterial vaginosis (BV) is one of the most common causes of abnormal vaginal discharge in women. The disease is characterized by an imbalance in the vaginal bacterial flora. We aimed to determine the frequency of Gardnerella vaginosis by cultivation and molecular method.

In summer 2019, the vaginal secretion of 110 women with BV were collected and isolated for G. vaginalis, in Isfahan. The isolates were identified by the biochemical test. Polymerase chain reaction (PCR) was performed to detect G. vaginalis in vaginal secretions. Antibiotic susceptibility of the isolates was evaluated by disc diffusion method.

Gardnerella vaginalis was isolated from five samples among the 110 patients with symptoms of BV by cultivation. Based on molecular identification, G. vaginalis was shown in 32 (29.1%) samples. G. vaginalis isolates were resistant to clindamycin (20%) and amoxicillin/clavulanic acid (80%). All the isolates were sensitive to Metronidazole. All women with this infection were married and most (43.8%) belonged to the 25-30 year-old age group. A significant difference was found between participants with positive clue cell (P<0.01) and pH>4.5 vaginal discharge (P<0.01) in the PCR-positive and the PCR-negative women.

High prevalence of Gardnerella vaginalis in women with vaginosis confirms the important role of bacteria in the incidence of BV. Identification of pathogenic agents of G. vaginosis using molecular methods and determining their antibiotic susceptibility pattern is essential for proper treatment in different societies.