Tinea capitis in adults.

BACKGROUND: Tinea capitis is caused by dermatophyte fungi that utilize keratin as a nutrient source.  Scalp erythema, scaling, andcrusting are typical signs of this disease.  Although most commonly seen in prepubescent children, tinea capitis can occur in adults.
RESULTS: Endothrix tinea capitis owing to Trichophyton tonsurans commonly produces generalized scaling and localized perifollicular inflammation reminiscent of lichen planopilaris. Ectothrix tinea capitis owing to Microsporum sp. produces well- demarcated erythematous plaques suggestive of psoriasis. H&E stained biopsy specimens, KOH preparations or fungal cultures will confirm the diagnosis.
CONCLUSION: Because of a low index of suspicion for tinea capitis in adults with scaling and alopecia, diagnosis and appropriate treatment are often delayed. Resistance to treatment for seborrheic dermatitis or psoriasis should prompt a KOH, fungal culture orbiopsy to confirm the diagnosis of tinea capitis and initiate systemic antifungal agents.