Piedra

(Figure 4.21C)
  • Superficial infection of hair shaft where fungal elements adhere to form nodes along hair shaft
  • Two types: black piedra and white piedra
    • Black piedra: Piedraia hortae; presents with tiny dark concretions on hairs shafts distributed irregularly; culture shows black velvety colony
    • White piedra: Trichosporon cutaneum (formerly T. beigelii ) most common; other species include T. ovoides, T. inkin, and T. asahii; presents with light brown, less adherent nodules coating hair shaft (beard, axilla, pubic hairs)
  • Of note, T. cutaneum can cause fungemia with systemic disease in immunocompromised patients
  • Treatment: shaving/cutting hair, topical imidazoles
   
 
Do not confuse trichosporon with “trichophyton”
 
   
Figure 4.21 A: Pityriasis versicolor (Courtesy of Dr. Paul Getz) B: Tinea nigra (Courtesy of Dr. Marcus Henrique de Sousa Brito Xavier, Brazil) C: Piedra (Courtesy of Doctor Fungus, www.doctorfungus.org)
Figure 4.21
A: Pityriasis versicolor
(Courtesy of Dr. Paul Getz)
B: Tinea nigra
(Courtesy of Dr. Marcus
Henrique de Sousa Brito
Xavier, Brazil
)
C: Piedra
(Courtesy of Doctor Fungus,
www.doctorfungus.org
)