Diagnosis
Seborrheic Dermatitis
Diagnosing seborrheic dermatitis typically involves a clinical evaluation of the affected areas by a dermatologist. The diagnosis is primarily based on the characteristic appearance and location of the lesions. Dermatologists look for specific symptoms such as red, scaly patches and dandruff. A skin biopsy may be performed if the diagnosis is uncertain or if other conditions are suspected. This biopsy would reveal specific histopathological features, including parakeratosis (retention of nuclei in the stratum corneum), plugged follicular ostia, and spongiosis (intercellular edema in the epidermis). The dermis typically exhibits a sparse, perivascular, lymphohistiocytic inflammatory infiltrate.
Differential diagnoses to consider include atopic dermatitis, psoriasis, fungal infections, and other conditions that present with similar symptoms. Dermatologists may also use dermoscopy to identify trichoscopic features specific to seborrheic dermatitis, such as perifollicular scaling and diffuse yellowish scales.
