Bacterial vaginosis in Portugal

: diagnosis of Gardnerella vaginalis and Atopobium vaginae in healthy or symptomatic women

Abstract

Bacterial vaginosis is the leading vaginal disorder, having an important impact worldwide. It is estimated to affect 30-50% of African-American women and 10-20% of Caucasian women at reproductive age. During bacterial vaginosis, a decrease of Lactobacillus spp. and an increase in the number of anaerobic microorganisms, such as Gardnerella vaginalis and Atopobium vaginae in the vaginal epithelium is observed. Although commonly associated to bacterial vaginosis, G. vaginalis has also been associated to the vagina of healthy women, but in lower numbers. The growth of G. vaginalis can be identified by beta hemolysis, variable Gram staining, negative oxidase and catalase (conventional microbiological tests) and by molecular techniques. The main goal of this study was the identification of G. vaginalis and A. vaginae in the vaginal microflora of healthy or ill women, by molecular techniques. The reason of our interest in these microorganisms was based on fact of being the mostly isolated microorganisms in cases of bacterial vaginosis. Gardnerella vaginalis and, most recently, A. vaginae were two microorganisms firstly associated to bacterial vaginosis, however more recent studies identified them on the healthy vaginal microflora. In Portugal, the unique study involving bacterial vaginosis was done in 1998, which consequently straighten up the importance of this study. By this way, our study involved the reception of swabs obtained by self-harvest, gynecological private practice or even in hospitals emergency and the posterior manipulation of the samples. The identification of G. vaginalis and A. vaginae was specially based on the analysis of the clinical samples by Polymerase Chain Reaction (PCR), and by Peptide Nucleic Acid Fluorescence in situ Hybridization (PNA-FISH). The results revealed that from fifty-seven Portuguese women samples involved in this study, the presence of G. vaginalis was detected in sixteen samples, which corresponds to a prevalence of 28 %. On the other hand A. vaginae was present in five clinical samples, which corresponds to 8 % of the samples. The molecular techniques allowed the direct identification of part of the microorganisms present on the vaginal swabs and allowed to conclude that the G. vaginalis and A. vaginae are not only associated to bacterial vaginosis but they can also be founded, in different percentage, in a range of Portuguese healthy women.

Date of Award	2012
Original language	English
Awarding Institution	Universidade Católica Portuguesa
Supervisor	Nuno Cerca (Supervisor) & Maria Manuela Pintado (Co-Supervisor)