Vulvovaginal candidiasis : histologic lesions are primarily polymicrobial and invasive and do not contain biofilms

BACKGROUND: The recent demonstration of a vaginal biofilm in bacterial vaginosis and its postulated importance in the pathogenesis of recurrent bacterial vaginosis, including relative resistance to therapy, has led to the hypothesis that biofilms are crucial for the development of vulvovaginal candidiasis. The histopathology and microbial architecture of vulvovaginal candidiasis have not been previously defined; neither has Candida, containing biofilm been reported in situ. The present study aimed at clarifying the histopathology of vulvovaginal candidiasis including the presence or absence of vaginal biofilm. STUDY DESIGN: In a cross-sectional study, vaginal tissue biopsies were obtained from 35 women with clinically, microscopically, and culture-proven vulvovaginal candidiasis and compared with specimens obtained from 25 healthy women and 30 women with active bacterial vaginosis. Vaginal Candida infection was visualized using fluorescent in situ hybridization with ribosomal gene-based probes. RESULTS: Candida microorganisms were confirmed in 26 of 35 biopsies obtained from women with vulvovaginal candidiasis; however, Candida containing biofilm were not detected in any of the cases. Histopathological lesions were exclusively invasive and accompanied by co-invasion with Gardnerella or Lactobacillus species organisms. CONCLUSION: Histopathological lesions of vulvovaginal candidiasis are primarily invasive in nature and polymicrobial and do not resemble biofilms. The clinical significance of Candida tissue invasion is unknown

Prevalence of macrolide and fluoroquinolone resistance-mediating mutations in Mycoplasma genitalium in five cities in Russia and Estonia.

Resistance in the sexually transmitted bacterium Mycoplasma genitalium to all recommended therapeutic antimicrobials have rapidly emerged. However, to date, internationally reported resistance surveillance data for M. genitalium strains circulating in Eastern Europe are entirely lacking. The aim of this study was to estimate the prevalence of macrolide and fluoroquinolone resistance-associated mutations in M. genitalium in four cities in Russia and one in Estonia, 2013-2016.Consecutive urogenital samples found positive for M. genitalium during diagnostic testing were retrospectively analyzed for resistance-associated mutations in the 23S rRNA and parC genes using pyrosequencing and conventional Sanger sequencing, respectively.In total, 867 M. genitalium positive samples from 2013-2016 were analyzed. Macrolide resistance-associated mutations were detected in 4.6% of the samples from Russia (0.7-6.8% in different cities) and in 10% of the samples from Estonia. The mutations A2059G and A2058G were highly predominating in both Russia and Estonia, accounting together for 90.9% of the cases positive for nucleotide substitutions in the 23S rRNA gene. The rates of possible fluoroquinolone resistance-associated mutations were 6.2% in Russia (2.5-7.6% in different cities) and 5% in Estonia. The mutations S83I and S83N were the most frequent ones in Russia (24.4% each), whereas D87N highly predominated in Estonia (83.3% of all fluoroquinolone resistance-associated mutations). Approximately 1% of the samples in both countries harbored both macrolide and possible fluoroquinolone resistance-associated mutations, with A2058G and S83I being the most frequent combination (37.5%).The prevalence of macrolide and fluoroquinolone resistance-associated mutations in M. genitalium was 4.6% and 6.2%, respectively, in Russia, and 10% and 5%, respectively, in Estonia. Despite the relatively low rates of macrolide and fluoroquinolone resistance in these countries, antimicrobial resistance surveillance and testing for resistance-associated mutations in M. genitalium positive cases would be valuable

Prevalence of <i>Mycoplasma genitalium</i> positive samples with multidrug resistance (both 23S rRNA gene and ParC mutations) in four cities in Russia and one city in Estonia.

<p>Prevalence of <i>Mycoplasma genitalium</i> positive samples with multidrug resistance (both 23S rRNA gene and ParC mutations) in four cities in Russia and one city in Estonia.</p

Prevalence of possible fluoroquinolone resistance-associated <i>parC</i> mutations (mutations in QRDR of <i>parC</i>) in <i>Mycoplasma genitalium</i> positive samples in four cities in Russia and one city in Estonia.

<p>Prevalence of possible fluoroquinolone resistance-associated <i>parC</i> mutations (mutations in QRDR of <i>parC</i>) in <i>Mycoplasma genitalium</i> positive samples in four cities in Russia and one city in Estonia.</p