Multilocus Genotyping Indicates that the Ability To Invade the Bloodstream Is Widespread among Candida albicans Isolates

Abstract

Multilocus genotyping was used to compare populations of Candida albicans from oral mucosa and blood. No significant differences in allele frequencies between the two samples were detected, and in a dendrogram of genotypic similarities, genotypes from both types of samples were finely interspersed. This is evidence for widespread distribution of invasive potential.

Genotyping of Candida albicans Oral Strains from Healthy Individuals by Polymorphic Microsatellite Locus Analysis

“…Our data indeed suggest that all commensal strains have the ability to develop as pathogens in nonhealthy individuals. This is consistent with the few studies we are aware of that have addressed the relationship between genotypes and commensalism or pathogenicity in C. albicans (3,12,21,23). In this context, our contribution is to present data based on three large series of independent strains that were clearly characterized in terms of the host-parasite relationship (commensal, colonizing, or bloodstream invasive).…”

“…Although three major genotypes were identified in the study, they were overrepresented in both bloodstream and nonbloodstream strains, and no pathogenic genotype, i.e., no genotype with a propensity for bloodstream invasion, was identified (7). This finding was subsequently confirmed by a multilocus comparison of bloodstream strains and oropharyngeal isolates from human immunodeficiency virusinfected patients (12). However, both studies compared series of strains obtained from nonhealthy individuals.…”

Usefulness of Multilocus Sequence Typing for Characterization of Clinical Isolates of Candida albicans

“…A multilocus genotyping system using oligonucleotide probes for identification of the nucleotide state at only one of the polymorphic nucleotide sites of each of 16 distinct loci distinguished only 64 genotypes in a sample of 84 C. albicans isolates (3). Recently, it was shown by this method that the ability to invade the bloodstream is widespread among C. albicans isolates (15). The discriminatory power of our MLST method was similar to that of fingerprinting with the moderately repetitive sequence Ca3, which provided the highest resolution reported so far for typing of C. albicans isolates (25).…”

Population genomics of drug resistance in Candida albicans

“…Thirty clinical isolates were screened for expression levels of the nine genes showing the largest change in expression in the microarray experiments (ADH4, MDR1, YPL88, YPX98, YPR127W, GRE99, YNL229C, HYR1, and HSP12) and for expression levels of CDR2. Twenty-nine isolates were from oral swabs from HIV-infected patients (19) and one (B1) was from a blood culture from a patient (20). These 30 isolates were selected because their MICs of fluconazole were Ն4 g͞ml.…”