Clinical Differential Diagnosis of Scalp Infection

Diagnosing scalp fungal infections, such as piedra and tinea capitis, is challenging due to their similarity to other conditions like pediculosis, trichorrhexis nodosa, monilethrix, and trichomycosis axillaris. Tinea capitis, in particular, presents in various forms, complicating differential diagnosis. Essential diagnostic tools include clinical evaluation, trichoscopy, and cultural samples. Trichoscopic indicators for tinea capitis include comma hair, broken hair with a constant diameter, black dots, and corkscrew hair, with scalp scaling being a common feature. It is crucial to differentiate these infections from seborrheic dermatitis, psoriasis, and contact dermatitis, as well as from alopecia areata and trichotillomania in cases lacking intense scales.