Dermatophytoses
Definitions
• All denote superficial fungal infections (mycoses) involving the stratum corneum, hair, or nails; more specifically termed dermatophytoses
• Tinea capitis describes dermatophyte infection of hair & scalp caused by Trichopyton & Microsporum species
• Tinea corporis refers to any dermatophytosis of glabrous (smooth, hairless) skin except palms, soles, & the groin region. Most commonly caused by T. rubrum.
• Tinea cruris is a dermatophytosis of the groin, genitals, pubic area, or perineum. Most commonly caused by T. rubrum or E. floccosum.
• Tinea pedis describes dermatophytosis of the feet, while tinea manuum involves the hand (commonly the palms or interdigital regions). Most commonly caused by T. rubrum, T. interdigitale, or E. floccosum.
• Tinea unguium/Onychomycosis describe fungal infections of the nail. Most commonly caused by T. rubrum, T. interdigitale, or E. floccosum.
Disposition
• Home w/ primary care or dermatology f/u
Pearls
• A dermatophytid, or Id, rxn may occur in pts w/ dermatophytoses & may represent a delayed-type hypersensitivity rxn to fungal antigens. Clinically, pts present w/ a primary dermatophytosis as well as papules or vesicles on the hands & feet that are often pruritic.
Tinea (Pityriasis) Versicolor
Definition
• Cutaneous infection caused by Malassezia species, which is normally found on skin surface thus, not considered contagious
History
• Subacute/chronic skin discoloration usually noticed by pt; mild pruritus
• RFs: Warm/humid environments, immunosuppression, OCP use, poor nutrition
Physical Findings
• Scaly oval-to-round macules or patches that are typically hypopigmented, but may also be hyperpigmented/salmon-colored distributed over neck, upper trunk, back, or arms
• Wood’s lamp exam may show yellow-orange fluorescence
• KOH prep w/ fungal spores & short hyphae; “spaghetti & meatballs” appearance
Treatment
• Topical: Selenium sulfide lotion 2.5% for 10 min before rinsing, 3–4 times weekly; also, zinc pyrithione, azole shampoos (ketoconazole 2%), terbinafine topical, ciclopirox
• Systemic (for extensive dz): Ketoconazole, itraconazole, fluconazole
Disposition
• Home
Pearls
• May be confused w/ vitiligo, pityriasis rosea, or dermatophytoses among others
• Regular maintenance application of above topical txs may prevent recurrence
Cutaneous Candidiasis and Intertrigo
Definition
• Fungal infection (mycosis) by any of the Candida species (C. albicans)
• C. albicans has a predilection for colonizing skin folds (intertriginous areas) where the environment is warm & moist
History
• Itching, burning, or asymptomatic rash in intertriginous areas (groin, axilla, web spaces, inflammatory areas, beneath the pannus, gluteal fold)
• RFs: Obesity, DM, occlusive clothing, immunosuppressive medications, poor hygiene
Physical Findings
• Moist, red, shiny macules/patches w/ scalloped borders, adjacent satellite pustules
Treatment
• Keep dry, topical antifungals (Various preparations: Creams, lotions, powders, with/without mild steroid combinations; poor data to support 1 type over the other)
Disposition
• Home