Candida galli as a Cause of Tinea Unguium—Molecular Characterization of a Rare Clinical Fungal Entity

Biological and genomic analyses of a clinical isolate of Yarrowia galli from China

Infections caused by emerging fungal pathogens represent a new threat to human health. The yeast Yarrowia (Candida) galli was first described from chicken breast and liver in 2004 and has occasionally been isolated in clinical settings. In this study, we present the first report of a Y. galli isolate from a face granuloma of a woman. Y. galli is unable to grow at human physiological temperature (37 °C). Phenotypic analysis demonstrates that Y. galli can exist as several morphological types, namely fluffy, sticky, tight, and yeast forms, based on their cellular and colony appearances. Interestingly, Y. galli is able to undergo switching among different morphologies. These morphological changes are similar to the switching systems in pathogenic Candida species such as Candida albicans and Candida tropicalis. We further sequenced the genome of the Y. galli isolate. A comparative analysis with pathogenic yeast species indicated that a set of lipid metabolism genes were enriched in Y. galli. Domain enrichment analysis demonstrated that, similar to Candida clade species, the genome of Y. galli maintained several gene families required for virulence. Our biological and genomic analyses provide new insights into the understanding of the biology of Y. galli as either an environmental isolate or a potential human pathogen.

Incidence and biodiversity of yeasts, dermatophytes and non-dermatophytes in superficial skin infections in Assiut, Egypt

OBJECTIVE

The aim was to identify the incidence of the causal agents from dermatophytes, non-dermatophytes and yeasts in Assiut Governorate employing, beside the morphological and physiological techniques, the genotypic ones.

PATIENTS

Samples from infected nails, skin and hair were taken from 125 patients.

MATERIALS AND METHODS

Patients who presented with onychomycosis, tinea capitis, tinea corporis, tinea cruris and tinea pedis during the period from February 2012 to October 2015 were clinically examined and diagnosed by dermatologists and were guided to Assiut University Mycological Centre for direct microscopic examination, culturing and identification.

RESULTS

Onychomycosis was the most common infecting (64.8% of the cases) followed by tinea capitis (17.6%). Direct microscopic preparations showed only 45 positive cases, while 96 cases showed positive cultures. Infections were more frequent in females than males. Fifty-one fungal species and 1 variety were obtained. Yeasts were the main agents being cultured from 46.02% of total cases. Non-dermatophytes were the second etiologic agents. Aspergillus was responsible for infecting 19.47% of total cases and dermatophytes appeared in only 15.93% of the cases.

CONCLUSIONS

Yeasts were the main causal agents followed by non-dermatophytic fungi (mainly species of Aspergillus, then Alternaria, Scopulariopsis and Fusarium). Both direct microscopic preparations and culturing are recommended for mycological evaluation of clinical specimens. Sequence analysis of ITS region is recommended for yeast identification.

Candida nivariensis as a New Emergent Agent of Vulvovaginal Candidiasis: Description of Cases and Review of Published Studies

Candida nivariensis is a new emergent agent related to human infections in the vaginal tract and other localizations, but the phenotypic characteristics are very similar to Candida glabrata and can be misidentified and underdiagnosed. We described four cases of vulvovaginitis identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry and confirmed the results with PCR amplification and sequencing of the entire ITS genomic region (ITS1, ITS2 and 5.8 rRNA). We reinforce the need for new diagnostic tools for the correct identification of yeast infections.