دانلود رایگان ترجمه مقاله حساسیت ضد میکروبی و واژینولیزین در Gardnerella vaginalis از زنان سالم (نشریه Jidc 2015)

حساسیت ضد میکروبی و واژینولیزین در Gardnerella vaginalis از زنان سالم و مبتلا به واژینوز باکتریال

Antimicrobial susceptibility and vaginolysin in Gardnerella vaginalis from healthy and bacterial vaginosis diagnosed women

Abstract

Introduction: Bacterial vaginosis (BV) is a syndrome related to Gardnerella vaginalis and is characterized by an imbalance in the vaginal microbiota. This work focused on the evaluation of antimicrobial susceptibility patterns and the occurrence of the vaginolysin (vly) gene in G. vaginalis isolated from BV and non-BV patients. Methodology: The vaginal secretions were collected randomly and processed for G. vaginalis isolation. The isolates were presumptively identified by β-hemolysis and oxidase and catalase tests. Polymerase chain reaction (PCR) was performed to confirm bacterial identity and to detect the vly gene. Antimicrobial susceptibility patterns were determined. Results: Of 89 patients, G. vaginalis was isolated from 42 (37 BV and 5 non-BV), and 204 isolates were selected (179 from BV and 25 nonBV). The vly gene was detected in all G. vaginalis isolated from non-BV women and in 98.3% of the bacteria from BV patients. High resistance was observed for ampicillin (54.4%), metronidazole (59.8%), tinidazole (60.3%) and secnidazole (71.6%). Conclusions: Further studies are needed to better address the role of G. vaginalis and the vly gene in BV pathogenesis.

۱ Introduction

Vaginal microbiota is defined as a diverse group of microorganisms that colonises the vagina without causing disease, considering the host’s regular homeostatic conditions [1]. Bacterial vaginosis (BV) is a polymicrobial syndrome mainly related to Gardnerella vaginalis, characterized by an imbalance in the healthy vaginal microbiota with an increase in anaerobic bacteria, particularly those producing H2O2, which leads to the onset of fetid vaginal discharge [2]. The prevalence of BV is difficult to determine, since a large proportion of infected women are asymptomatic and do not seek medical care, and are not therefore included in the studies. BV is the most common cause of vaginal discharge in women of reproductive age and is more common in black women than white, in those women with intrauterine devices (IUDs), in smokers, in women with multiple sexual partners, and in patients using antibiotics [3]. Anaerobic microorganisms associated with BV mainly include G. vaginalis, Ureaplasma urealyticum, M. hominis, Mobiluncus spp., Bacteroides spp., and Prevotella spp. The microorganisms involved and their products differ significantly between women with BV, and the risk of upper genital tract infections also probably varies between individuals [4]. The isolation of G. vaginalis may not be used for BV diagnosis because it is part of the vaginal microbiota of more than 50% of healthy women. A high concentration of G. vaginalis is often associated with the presence of BV [1].

As the clinical diagnosis of BV has been shown to be vulnerable, different methods have been proposed, such as those of Amsel and Nugent, which include clinical and laboratory observations [5]. Amsel criteria is used as the main clinical approach to BV diagnosis and requires three of the following four criteria: vaginal pH higher than 4.5; presence of adherent white vaginal discharge; finding of vaginal epithelial cells covered with adherent bacteria, the clue cells; and release of volatile amines following the addition of potassium hydroxide to a small amount of vaginal fluid [5,6]. As an alternative to the clinical diagnosis based on Amsel criteria, the Nugent score has been proposed to evaluate the vaginal microbiota through examination of vaginal smears under a microscope [7,8].