Evaluation of the CHROMagar Candida Plus medium for presumptive identification of yeasts and MALDI-TOF MS identification.

Rapid and accurate yeasts species identification in clinical laboratories is important for appropriate and timely antifungal treatment. We evaluate the performance of the new medium CHROMagar™ Candida Plus for presumptive identification of yeasts species and MALDI-TOF identification. We identify 303 strains belonging to 60 clinically relevant yeasts species by using the new medium.

Genotypic Diversity and Antifungal Susceptibility of Clinical Isolates of Cryptococcus Gattii Species Complex from Argentina.

The aim of this study was to determine the genotypic diversity of 22 Cryptococcus gattii species complex clinical isolates from Argentina and to place these genotypes within the diversity of clinical, veterinary and environmental isolates from Latin America. Mating type and antifungal susceptibility of the isolates were also determined. By URA5-RFLP, nine isolates were identified as molecular type VGI, 10 as VGII, one as VGIII and two as VGIV.

Phylogenomic Placement of American Southwest-Associated Clinical and Veterinary Isolates Expands Evidence for Distinct VGVI.

Whole-genome sequencing has advanced our understanding of the population structure of the pathogenic species complex Cryptococcus gattii, which has allowed for the phylogenomic specification of previously described major molecular type groupings and novel lineages. Recently, isolates collected in Mexico in the 1960s were determined to be genetically distant from other known molecular types and were classified as VGVI. We sequenced four clinical isolates and one veterinary isolate collected in the southwestern United States and Argentina from 2012 to 2021.

Effectiveness of the National Quality Control Program in Mycology of Argentina and performance evaluation of participating laboratories.

The National Quality Control Program in Mycology (PNCCM) of Argentina was established in 1996 to improve the quality of the mycological diagnosis, to help establish and to set up standardized procedures and continuous training of laboratory staff. The aim of this study was to assess the effectiveness of the PNCCM in the 1996-2018 period. Data from the National Mycology Laboratory Network (NMLN) and PNCCM database was used to estimate the increase in the number of controlled laboratories and jurisdictions, the percentage of participation, the improvement in the quality of results and the adherence to the program.

Frequency and geographical distribution of genotypes and mating types of Cryptococcus neoformans and Cryptococcus gattii species complexes in Argentina.

The aim of this work was to know the frequency and geographical distribution of genotypes and mating types of Cryptococcus neoformans and Cryptococcus gattii species complexes isolated from human infections in Argentina during the period from April 2009 to April 2011. A multicenter study was conducted, in which 372 isolates were obtained from 61 laboratories throughout the country. Of those, 98.

First case report of cryptococcosis due to Cryptococcus decagattii in a pediatric patient in Argentina.

We report the first case of cryptococcosis due to Cryptococcus decagattii in an immunocompetent pediatric patient from an indigenous community in Argentina with a successful outcome. Two isolates (blood, cerebrospinal fluid) were genotyped by restriction fragment length polymorphism of the orotidine monophosphate pyrophosphorylase (URA5) gene as VGIV and identified by multi-locus sequence typing as C. decagattii.

First bloodstream infection due to var. in an immunocompromised patient.

Here we describe a bloodstream infection due to var in a patient with acute lymphoblastic leukemia. Identification was performed by DNA sequencing of the D1/D2 domain of 26s ribosomal DNA and by MALDI-TOF MS technique. Antifungal susceptibility tests against amphotericin B, fluconazole, itraconazole, and voriconazole showed the following MIC values, respectively: 0.

National production of certified reference fungal cultures.

Reference fungal cultures (RFCs) are essential for the internal quality control of laboratories. The production of these cultures requires standardized procedures (IRAM 14950:2016 and ISO 17034:2016 standards) carried out by a recognized and accredited laboratory. The aim of this work was to produce RFC in paper disks of autochthonous strains, characterized by two, homogeneous and stable reference methods traceable at species level.

Reidentification and antifungal susceptibility profile of Candida guilliermondii and Candida famata clinical isolates from a culture collection in Argentina.

The aim of this work was to reidentify strains previously identified as Candida guilliermondii and Candida famata by conventional phenotypic methods conserved in a culture collection from Argentina using ribosomal DNA sequencing, ACT1 gene sequencing, and matrix-assisted laser desorption ionization - time of flight mass spectrometry (MALDI-TOF MS). In addition, we performed antifungal susceptibility tests of eight antifungal drugs commonly used in clinical treatment. We identified 68 isolates belonging to the Candida guilliermondii species complex (59 C.

Development and validation of an extended database for yeast identification by MALDI-TOF MS in Argentina.

Matrix-assisted laser desorption/ionization-time of flight mass spectrometry (MALDI-TOF MS) has revolutionized the identification of microorganisms in clinical laboratories because it is rapid, relatively simple to use, accurate, and can be used for a wide number of microorganisms. Several studies have demonstrated the utility of this technique in the identification of yeasts; however, its performance is usually improved by the extension of the database. Here we developed an in-house database of 143 strains belonging to 42 yeast species in the MALDI Biotyper platform, and we validated the extended database with 388 regional strains and 15 reference strains belonging to 55 yeast species.

Candida glabrata species complex prevalence and antifungal susceptibility testing in a culture collection: First description of Candida nivariensis in Argentina.

The presence of the cryptic species belonging to the Candida glabrata complex has not been studied in Argentina. We analyzed a collection of 117 clinical isolates of C. glabrata complex belonging to a National Culture Collection of Instituto Nacional de Microbiología "Dr.

Amino acid substitution in Cryptococcus neoformans lanosterol 14-α-demethylase involved in fluconazole resistance in clinical isolates.

The molecular basis of fluconazole resistance in Cryptococcus neoformans has been poorly studied. A common azole resistance mechanism in Candida species is the acquisition of point mutations in the ERG11 gene encoding the enzyme lanosterol 14-α-demethylase, target of the azole class of drugs. In C.

First Case of Fungemia Due to Pseudozyma aphidis in a Pediatric Patient with Osteosarcoma in Latin America.

We report the first case of blood infection due to Pseudozyma aphidis in Latin America. We contribute evidence showing this organism to be a potential human pathogen, and we provide new data about its identification, drug susceptibility, and treatment outcome.

Molecular identification, genotyping, and antifungal susceptibility testing of clinically relevant Trichosporon species from Argentina.

Trichosporon species are emerging causative agents of mycoses; most are documented in immunocompromised patients. Species identification is important for epidemiological purposes in order to better define species clinical associations and to improve antifungal treatment. Here, we studied a collection of 41 Trichosporon strains recovered from hospitalized patients in Argentina.

Cryptococcus gattii in urban trees from cities in North-eastern Argentina.

In the city of Buenos Aires, Argentina, Cryptococcus gattii genotype AFLP4/VGI was found to be associated with decaying wood in hollows of different tree species. The aim of this study was to investigate the presence of C. gattii in the environment of riverside cities of the river Paraná, and to describe its serotypes and molecular types.

Comparative analyses of classical phenotypic method and ribosomal RNA gene sequencing for identification of medically relevant Candida species.

As the distribution of Candida species and their susceptibility to antifungal agents have changed, a new means of accurately and rapidly identifying these species is necessary for the successful early resolution of infection and the subsequent reduction of morbidity and mortality. The current work aimed to evaluate ribosomal RNA gene sequencing for the identification of medically relevant Candida species in comparison with a standard phenotypic method. Eighteen reference strains (RSs), 69 phenotypically identified isolates and 20 inconclusively identified isolates were examined.

First case report of bloodstream infection due to a Candida species closely related to the novel species Candida pseudorugosa.

Candida pseudorugosa is a novel species closely related to Candida rugosa for which only one case has been reported. We report the first case of a bloodstream infection in humans caused by a Candida sp. closely related to C.

Prevalence of Candida dubliniensis fungemia in Argentina: identification by a novel multiplex PCR and comparison of different phenotypic methods.

Candida dubliniensis is an emerging pathogen that can cause invasive disease in patients who have a variety of clinical conditions. C. dubliniensis is often misidentified as Candida albicans by clinical laboratories.