White piedra: ultrastructure and a new micro-ecological aspect

Area of Science:

• Dermatology
• Mycology
• Microbiology

Background:

• White piedra is a superficial fungal infection affecting hair shafts, caused by Trichosporon beigelii.
• This condition is globally distributed and can impact hair on any part of the body.

Purpose of the Study:

• To report a case of white piedra occurring on the inguinal hair.
• To conduct ultrastructural studies of the fungal nodules.
• To investigate potential sources of reinfection or therapeutic failure.

Main Methods:

• Transmission electron microscopy (TEM) was used to examine the morphology of fungal nodules.
• Scanning electron microscopy (SEM) was employed to observe spore elimination and examine infected cotton fibers.
• Comparative analysis of fungal structures in vivo and in vitro.

Main Results:

• TEM revealed fungal hyphae and arthrospores within the nodules, along with a unique cementant substance.
• SEM demonstrated spore extrusion from nodule surfaces.
• Identical nodules were observed on the patient's cotton underwear fibers via SEM.

Conclusions:

• The presence of similar fungal nodules on clothing provides a potential explanation for persistent or recurrent white piedra infections.
• Therapeutic strategies for white piedra should consider environmental contamination, particularly clothing.
• Strict hygienic measures, including proper laundering and disinfection of garments, are crucial for successful treatment and prevention of recurrence.