PetriKey

Fungus

Trichosporon species

Arthroconidia-forming yeast; white piedra

trik-oh-SPOR-on

yeastarthroconidiasuperficialopportunisticneutropeniatrichosporon

High-yield clue

Arthroconidia-forming yeast causing soft hair-shaft nodules (white piedra), plus a false-positive cryptococcal antigen in disseminated disease, is the core study clue.

Overview

Yeast-like fungi (notably Trichosporon asahii) that form true hyphae and arthroconidia; they cause superficial white piedra of hair and disseminated trichosporonosis in neutropenic hosts. Classic arthroconidia-forming yeast teaching organism.

Classification

  • Yeast-like fungus
  • Basidiomycota
  • Produces true hyphae, pseudohyphae, and arthroconidia
  • Blastoconidia present
  • Environmental and skin-associated

Lab & identification clues

  • Hyaline arthroconidia (segmenting hyphae) microscopy vocabulary
  • Soft light nodules on hair shafts in white piedra
  • Cross-reacts with cryptococcal antigen test vocabulary
  • Growth as urease-positive yeast in coursework

Associations

  • White piedra of scalp, beard, or body hair vocabulary
  • Disseminated trichosporonosis in neutropenic/hematologic patients
  • Bloodstream and catheter-related infection vocabulary
  • Summer-type hypersensitivity pneumonitis association

Commonly confused with

  • Cryptococcus (shared antigen cross-reaction)
  • Geotrichum (arthroconidia-forming look-alike)

Your notes

Original student-study summary. Sources checked: OpenStax Microbiology 2e, NCBI Bookshelf Medical Microbiology, and CDC topic pages where applicable; reviewed 2026-06. Educational only; no diagnosis, treatment, dosing, or specimen-handling guidance.

OpenStax: Microbiology 2e organism classification foundationssourceNCBI Bookshelf: Medical Microbiology organism chapterssourceCDC: CDC disease and public-health topic pagessource