Resident Editor: Michelle Matzko MD, Ph.D.
Faculty Editor: Ryan Arakaki, M.D.
BOTTOM LINE ✔ KOH prep for immediate diagnosis ✔ Certain tinea infections (hair, nails, hands) require oral antifungals |
Background
- Caused by three genera of fungi: Trichophyton, Epidermophyton, Microsporum
- Fungi multiply within keratinized tissue (hair, skin, nails)
- Transmission can be human-to-human, animal-to-human, or soil-to-human
- The infected epidermis of the body (tinea corporis), groin (tinea cruris), face (tinea faciei), scalp (tinea capitis), feet (tinea pedis), hands (tinea manuum), nails (tinea unguium), the hair follicle (Majocchi’s granuloma)
- All forms except for tinea capitis occur more commonly in adults
Signs and Symptoms
- Classic lesion: Annular patch or plaque with overlying scale and an active, erythematous border
- Tinea capitis: Presents as alopecia with or without scale or alopecia with black dots at follicular orifices (broken hairs); severe cases can develop into kerion (boggy, elevated, tender nodules) or yellow crusting
- Tinea manuum: Diffuse scaling of palms and digits resistant to emollients; look for collarettes of scale
- Tinea pedis: Can be moccasin, interdigital, inflammatory, or ulcerative; often associated with tinea manuum, cruris, and unguium. Risk factor for cellulitis.
- Majocchi’s granuloma: follicular (non-scalp) involvment
Evaluation
- Tinea pedis, manuum, corporis, faciei, cruris:
- Typically diagnosed by KOH prep of the skin
- A biopsy will show hyphae in the stratum corneum (highlighted by PAS stain)
- Note: tinea cannot grow on the penis or scrotum
- Tinea unguium:
- Nail plate specimen with hyphae on KOH or PAS stain
- Nail bed debris for fungal culture (agar plate)
Treatment
- Tinea pedis, corporis, faciei, cruris:
- Topical antifungals
- Oral antifungals if severe or recalcitrant
- Tinea manuum, capitis, unguium; Majocchi’s granuloma: Need oral antifungals (see Table 3)
- Nystatin is useful for cutaneous candida infections but not for the treatment of dermatophytes
- Patients should not be treated with oral ketoconazole: risk of liver injury, adrenal insufficiency, drug interactions
- Avoid using combination (steroid+antifungal) products
- Steroids can exacerbate tinea infections and contribute to treatment failure
- Treatment can be prolonged and puts patients at risk for steroid side effects like skin thinning
Table 3: Treatments for tinea manuum, unguium, capitis, and pedis (bold is first-line)
|
Itraconazole |
Fluconazole |
Terbinafine |
Tinea manuum |
400 mg/d x 1 week |
150-200 mg/wk x4-6 wks |
250 mg/d x 2-4 wks |
Tinea unguium |
200 mg/d x 12 weeks |
150-200 mg/wk x 9 mos |
250 mg/d x 12 wks |
Tinea capitis |
5 mg/kg/d x 4-8 wks |
6 mg/kg/day x 3-6 wks |
250 mg/d x 2-4 wks |
Tinea pedis |
200mg bid x 1 week |
150mg/week x 2-6 wks |
250 mg/d x 2 wks |
For tinea capitis, griseofulvin is alternative first line therapy
For tinea pedis and manuum, can trial topical azoles first (once or twice daily for 4 weeks) or topical terbinafine 1% cream daily for one week.
El-Gohary, M; van Zuuren EJ, Fedorowicz Z et al. Topical antifungal treatments for tinea cruris and tinea corporis. Cochrane Database Syst Rev 2014 Aug 4; (8).