Cutaneous Flashcards
What does “tinea” mean?
Clinical name given to dermatophytes – cutaneous fungal infection.
What are Microsporum, Trichophyton, and Epidermophyton examples of?
dermatophytes.
What do dermatophytes look like histologically?
Branching septate hyphae visible on KOH prep w/ blue fungal stain.
What dermatophyte occurs on head/scalp? What else is is associated with?
Tinea capitis. LAD, alopecia, scaling.
What dermatophyte is associated with erythematous scaling rings w/ central clearing?
“ringworm”: tinea corporis. Occurs on body.
What kind of transmission can tinea corporis be associated with?
Contact from infected cat/dog.
What kind of dermatophyte infxn occurs in the inguinal area? how does it differ from ringworm?
Tinea cruris. Often does not show central clearing that occurs in tinea corporis.
What are the three varieties of tinea pedis?
Interdigital (most common)
Moccasin distribution
Vesicular type
What is onychomycosis?
Tinea inguium
What is tinea versicolor caused by?
Malassezia spp (pityrosporum spp), a yeast-like fungus (not a dermatophyte).
How does tinea versicolor cause sx?
Degradation of lipids produces acids that damage melanocytes and cause hypopigmented and/or pink patches - do not tan.
How does tinea versicolor appear on microscopy?
“Spaghetti and meatballs” - short, curved, unbranched hyphae with spherical yeast cells.
When is tinea versicolor more common?
Can happen anytime but more common in hot/humid weather.
