Candidiasis During Pregnancy May Result From Isogenic Commensal Strains

Abstract

Objective: Our laboratory previously demonstrated that asymptomatic vaginal colonization during pregnancy is a factor predisposing patients to subsequent symptomatic vulvovaginal candidiasis. It is unknown whether symptoms result from strain replacement or a change in host relationship to the original colonizing strain. This study was undertaken to determine whether Candida albicans isolates from asymptomatic women could be responsible for subsequent symptomatic vaginitis. Methods: We retained isolates of C. albicans from women followed longitudinally through pregnancy, and identified six pairs of cultures from women who were colonized without symptoms and who later became symptomatic (average time 14 weeks). We used a random amplification of polymorphic DNA (RAPD) analysis to determine whether isolates from our study patients were genetically similar or dissimilar. Results: Analysis of these pairs of yeast strains by RAPD revealed that five of the six women had symptoms apparently due to the same yeast strain that was found initially as a commensal strain. To increase the power of these observations, we also performed RAPD analysis on six randomly selected yeast strains from other women in this study who had not become symptomatic to determine whether any of these unrelated strains matched strains from those women who became symptomatic. Conclusion: Symptomatic yeast vaginitis is usually due to strains of C. albicans already carried in the lower genital tract, underscoring the need to understand regulation of growth and virulence of the organism in vivo. Key words: VAGINITIS, MOLECULAR EPIDEMIOLOGY, PREGNANCYCandida albicans is recognized both as normal flora in the female genital tract and as the causative agent of vulvovaginal candidiasis. What is not clear is whether the vaginal commensal organism increases its virulence to cause candidiasis, the host becomes more permissive toward proliferation of the organism resulting in symptoms, or whether another, possibly more virulent, strain supplants the normal flora organism. The availability of methods of DNA analysis that distinguish between different strains makes it possible to obtain insight into this question.Soll has recently reviewed the myriad genotyping techniques available to raise epidemiologic investigations of C. albicans from the phenotypic to the genotypic level 1 . These techniques have allowed the tracking of transmission of organisms within families, from mothers to infants and within Infect Dis Obstet Gynecol 2001;9:65-73 Correspondence to: Bryan Larsen, PhD, Des Moines University Osteopathic Medical Center, 3200 Grand Avenue, Des Moines, IA 50312. E-mail: bryan.larsen@dmu.edu Clinical study 65hospital environments, and the association of genetic fingerprints with virulence and drug resistance. Genotyping approaches are of particular interest to organisms such as C. albicans, which can and often do colonize individuals in an asymptomatic fashion. One of the key questions arising from this observation is whether symptomatic candidiasis result...

A murine model for catheter-associated candiduria

“…However, molecular typing of Candida strains derived from vagina and urine has established a clonal relationship (Daniels et al, 2001;Silva et al, 2007) and supports the notion that candiduria similar to bacterial UTIs is mostly an 'ascending' infection and not the result of haematogenous invasion of the urinary-tract system. In hospitalized patients, ascending persistent candiduria in the setting of indwelling urine-draining devices is a very common entity, for which a murine model has not been established to date.…”

Candida Infections of the Genitourinary Tract

“…Molecular typing of Candida strains derived from the vaginas of pregnant women indicated that the women, who were followed longitudinally through pregnancy, became symptomatic (average time, 14 weeks) with their colonizing Candida strains (62). That study found that five of the eight patients with positive vaginal secretions later showed the presence of the same yeast species in their urine.…”

SSD1 Is Integral to Host Defense Peptide Resistance in Candida albicans

“…This paradigm is based on multiple lines of evidence as follows: (i) colonization precedes and is an independent risk factor for disseminated candidiasis (16,21,28,37), (ii) colonization burden correlates with the risk of invasive disease (6,8,22), and (iii) measures that reduce colonization burden reduce the subsequent risk of fungemia (18,29). Innate immunity plays a crucial role in controlling candidal colonization and preventing invasive candidiasis.…”

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