Detection of TR/L98H Mutation through Passive Surveillance for Azole-Resistant Aspergillus fumigatus in the United States from 2015 to 2017.

The emergence of azole-resistant has become a clinical problem in many parts of the world. Several amino acid mutations in the azole target protein Cyp51Ap contribute to this resistance, with the most concerning being the environmentally derived TR/L98H and TR/Y121F/T289A mutations. Here, we performed passive surveillance to assess a sample of the population in the United States for the presence of these mutations.

Candida lusitaniae MICs to the echinocandins are elevated but FKS-mediated resistance is rare.

MIC values were generated for caspofungin, micafungin, and anidulafungin against 106 isolates of C. lusitaniae, and these values were compared to established epidemiologic cutoff values. The majority of isolates were wild type both by MIC value as well as by FKS1 hotspot sequencing.

Role of FKS Mutations in Candida glabrata: MIC values, echinocandin resistance, and multidrug resistance.

Candida glabrata is the second leading cause of candidemia in U.S. hospitals.

Development of a Luminex-based multiplex assay for detection of mutations conferring resistance to Echinocandins in Candida glabrata.

Echinocandins are the recommended treatment for invasive candidiasis due to Candida glabrata. Resistance to echinocandins is known to be caused by nonsynonymous mutations in the hot spot-1 (HS1) regions of the FKS1 and FKS2 genes, which encode a subunit of the β-1,3-glucan synthase, the target of echinocandins. Here, we describe the development of a microsphere-based assay using Luminex MagPix technology to identify mutations in the FKS1 HS1 and FKS2 HS1 domains, which confer in vitro echinocandin resistance in C.

Validation of 24-hour flucytosine MIC determination by comparison with 48-hour determination by the Clinical and Laboratory Standards Institute M27-A3 broth microdilution reference method.

Flucytosine and itraconazole are the only antifungal agents for which the Clinical Laboratory and Standards Institute recommendations include MIC breakpoint readings at 48 h only. Here we show good essential and categorical agreement between the flucytosine MIC readings at 48 and 24 h for Candida species.

The human commensal yeast, Candida albicans, has an ancient origin.

Candida albicans, the primary causative agent of candidiasis, is a ubiquitous member of the human flora and is capable of causing severe invasive disease. Despite its importance as a human pathogen, little is known concerning those factors creating and maintaining genetic diversity within the species and how extant strains reflect their evolutionary history. Based on nucleotide polymorphism frequencies, we estimated the time to a most recent common ancestor for the species to be about 3-16 million years, with variation due to molecular clock calibration.

Evidence for aneuploidy and recombination in the human commensal yeast Candida parapsilosis.

Isolates of Candida parapsilosis, including representatives of the three major sub-species groups, were screened for single nucleotide polymorphisms (SNPs) by sequencing five independent loci totaling 4kb per isolate. Group I isolates were highly conserved and in some cases, group I alleles were found in group II and III strains. Unique alleles were also associated with groups II and III, consistent with earlier observations of intergroup divergence.