Clinical Differential Diagnosis of Scalp Infection

Differential diagnosis of scalp fungal infections, such as piedra and tinea capitis, is challenging due to their similar presentations to other conditions like pediculosis, trichorrhexis nodosa, monilethrix, and trichomycosis axillaris. Tinea capitis, in particular, can appear in various forms, complicating diagnosis. Essential diagnostic tools include clinical evaluation, trichoscopy, and cultural samples. Trichoscopic features like comma hair, broken hair with a constant diameter, black dots, and corkscrew hair are indicative of tinea capitis, with scalp scaling being a common symptom. It is crucial to differentiate these infections from seborrheic dermatitis, psoriasis, and contact dermatitis, which also present with scaling, as well as from alopecia areata and trichotillomania in cases without intense scales.