Genetic relatedness among vaginal and anal isolates of Candida albicans from women with vulvovaginal candidiasis in north-east Brazil

Abstract

Vulvovaginal candidiasis (VVC) is one of the most common causes of vaginitis and affects about 75 % of women of reproductive age. In order to better understand the epidemiology and pathogenesis of this disease, we evaluated genetic relatedness among 62 clinical isolates of Candida albicans sequentially obtained from the anus and vagina of patients with sporadic and recurrent VVC. Evaluation of patients' demographic and clinical data, direct examination, and colony forming units (c.f.u.) counts of vaginal and anal samples were also performed. The genotypes of strains were determined with ABC genotyping and Randomly Amplified Polymorphic DNA (RAPD). Genotype A was the most prevalent (93.6 %), followed by genotype C (6.4 %), whereas genotype B was not found. We found the maintenance of the same ABC genotype, regardless of the body site of each patient. Most of the vaginal strains suffered microevolution, whereas most of the anal strains were replaced during the period of study. Vaginal and anal isolates of C. albicans obtained simultaneously from the same patient showed the same ABC genotype and high genetic similarity as determined by RAPD. Genotype A seemed to be dominant in both vaginal and anal isolates of patients with VVC. Our results corroborate the hypothesis that there are 'substrains' of the C. albicans vaginal clone successfully established, which dominate in an apparently random manner over the course of time. It is suggested that the anal reservoir constitutes a possible source for vaginal infection in most of the cases.

Sexual behaviour and extra‐genital colonisation in women treated for recurrent Candida vulvo‐vaginitis

“…As this was not the aim of this study, we did not analyse the genetic association among Candida strains during all visits in all body sites. Previous research reveals the genetic relatedness between the anal and vaginal stains for RVVC patients . Despite that, sexual behaviour with possible re‐transmission was not a risk factor for poor response in our study.…”

“…Also, sexual transmission of Candida from anus to vagina by receiving anal intercourse did not seem to influence response to maintenance treatment. The anus is an important reservoir of Candida for RVVC patients not receiving suppressive therapy . However, according to our findings, during fluconazole maintenance therapy, casual anal intercourse is less evident as a risk factor for recurrence of Candida vulvovaginitis.…”

“…The anus is an important reservoir of Candida for RVVC patients not receiving suppressive therapy. 12 However, according to our findings, during fluconazole maintenance therapy, casual anal intercourse is less evident as a risk factor for recurrence of Candida vulvovaginitis. Only one patient with regular anal sex and only two of with casual anal sex did not respond to the treatment regimen.…”

“…15 Women had the same strains in different part of their bodies as well. 12 However, contrary to bacterial vaginosis, 16 sexual transmission of Candida could not be documented among women who have sex with women. 7 Also, the level of Candida colonisation was not related to sexual intercourse.…”

Clinical and molecular characteristics of bloodstream infections caused by Candida albicans in children from 2003 to 2011

“…In addition to MLST, the methods include polymerase chain reaction M A N U S C R I P T A C C E P T E D ACCEPTED MANUSCRIPT 15 fingerprinting and random amplification of polymorphic DNA [39], restriction fragment length polymorphism analysis [40], pulsed-field gel electrophoresis (PFGE) [19], and Southern blot hybridization with discriminating probes [38]. The strengths of MLST are not only a highly discriminative tool in analyzing the genetic relatedness among sequential isolates from the same or different study sites, but also allowing the inter-laboratory comparison worldwide.…”