1 Skin

Skin diseases are very frequent in children. Most of them, including the most common disorders, such as atopic dermatitis, hemangiomas, nevi, acne, or bacterial and viral infections, are readily diagnosed through an adequate anamnesis and clinical examination. However, some skin tumors and inflammatory disorders may require a biopsy. The patient’s age and relevant clinical history, in addition to the site from which the skin biopsy was obtained, should be known by the pathologist. A sound basis of pediatric dermatological epidemiology is necessary, since the entities most frequently observed in children differ significantly from those seen in adults. The specimens and biopsies most frequently sent for histopathological analysis in children are melanocytic nevi, inflammatory dermatoses such as Henoch– Schönlein purpura, psoriasis, pityriasis lichenoides, pityriasis rosea, lichen planus, pityriasis rubra pilaris, erythema multiforme, atopic dermatitis, granuloma annulare, and pigmented purpuric dermatosis, as well as infections, vascular anomalies and benign tumors/hamartomas/cysts. Genodermatosis and malignancies are rarely seen. In this chapter, we will be dealing with the histopathology features of the most commonly biopsied skin diseases in children.