White piedra: fungal extracellular matrix formation and its importance in pathogenesis. An ultrastructural study
Year: 2025
Type: article
Abstract: BACKGROUND: White piedra is a disease caused by some species of the genus Trichosporon. A case of white piedra was investigated, whose molecular examination identified Cutaneotrichosporon (Trichosporon) debeurmannianum as the causative agent. METHODS: Scanning electron microscopy (SEM) was used to examine the affected hairs, as well as the fungal colony of C. debeurmannianum obtained from the hairs. For comparative purposes, a colony of Trichosporon mucoides obtained from a mycotheque was also examined. RESULTS: Examination of the affected hairs using SEM easily demonstrates nodules on the hair shaft with a predominance of rounded yeast-like structures, adhered to each other by a cementing substance. Examination of the C. debeurmannianum colony demonstrates significant adhesion between the fungal cells by a reticular extracellular matrix. Examination of the T. mucoides colony obtained from a mycotheque demonstrates a small production of fibrillar substance between the blastoconidia. DISCUSSION: Examination of the colony obtained from the piedra showed significant formation of extracellular matrix, adhering to and covering the fungal structures, forming a biofilm. This matrix must correspond to the cementing substance described in the condition. CONCLUSION: The synthesis of the extracellular matrix must be crucial in the formation of white piedra nodules.
Language: English
Topic: Nail Diseases and Treatments
Subfield: Epidemiology
Field: Medicine
Domain: Health Sciences
Open Access status: gold
Estimated APC paid: $1,700
OpenAlex ID: W4411997350