Molecular identification of yeasts from the order Trichosporonales causing superficial infections

Area of Science:

• Medical Mycology
• Molecular Biology
• Infectious Diseases

Background:

• The order Trichosporonales was reclassified into three genera: Cutaneotrichosporon, Trichosporon, and Apiotrichum.
• Accurate identification of Trichosporonaceae is critical due to varying antifungal susceptibility profiles.
• Trichosporonosis etiology in Mexico is poorly understood, with reliance on phenotypic identification methods.

Purpose of the Study:

• To perform molecular-level identification of 12 yeast isolates morphologically consistent with Trichosporon.
• To identify yeasts obtained from patients diagnosed with superficial infections.

Main Methods:

• Morphological and genotypic identification of yeast isolates from patients with white piedra, onychomycosis, and dermatomycosis.
• Sequencing of the IGS1 region and phylogenetic analysis using the Maximum Likelihood Method.
• Phylogenetic analysis included 40 Trichosporonales sequences and one Cryptococcus neoformans outgroup.

Main Results:

• Molecular analysis identified three Trichosporon inkin (25%), two Trichosporon asteroides (16.7%), and two Cutaneotrichosporon mucoides (16.7%) isolates.
• Other identified species included Trichosporon aquatile, Trichosporon asahii, Apiotrichum montevideense, Cutaneotrichosporon cutaneum, and Cutaneotrichosporon jirovecii.
• A broad diversity of species within Trichosporonales was observed, particularly in onychomycosis cases.

Conclusions:

• Molecular characterization revealed significant species diversity within the order Trichosporonales.
• Species-level identification is essential for a deeper understanding of the epidemiology of these fungi.
• This study highlights the importance of molecular techniques for accurate fungal identification in clinical settings.