Subcorneal Pustular Dermatosis in Childhood: A Case Report and Review of the Literature

Subcorneal pustular dermatosis (SCPD, also known as Sneddon-Wilkinson disease) is a rare, benign, chronic, sterile pustular eruption which usually develops in middle-age or elderly women; it is rarely seen in childhood and adolescence. The primary lesions are pea-sized pustules classically described as half-pustular, half-clear flaccid blisters. Histologically the most important feature is a subcorneal accumulation of neutrophils with the absence of spongiosis or acantholysis, although acantholysis may be reported in older lesions. In this paper we present the case of a 7-year-old boy diagnosed with SCPD based on the characteristic clinical and histological features. Dapsone has been successfully used in the treatment of the disease. 1. Introduction Subcorneal pustular dermatosis (SCPD, Sneddon-Wilkinson disease) is a rare chronic, relapsing, pustular eruption that was first described by Sneddon and Wilkinson in [1]. It has been reported more frequently in women in the age group 40–50 years, however this disease can occur more rarely during the childhood [2]. Patients characteristically have a history of a relapsing symmetrical sterile pustular eruption involving the trunk, intertriginous areas, and flexor aspects of the limbs. The face, palms, soles, and mucous membranes are usually spared. The primary lesion is a small pustule arising on normal skin or slightly erythematous base. The pustules classically are described as half-pustular, half-clear fluid blisters that coalesce to form annular or serpiginous patterns. They are flaccid and rupture easily, resulting in superficial scaling, crusting, and faint hyperpigmentation. The condition is benign unless associated with underlying malignancy, which worsens the prognosis [3]. Its exact pathophysiology is unknown and its exact nosological classification is still controversial. The salient histological feature is a subcorneal accumulation of neutrophils with the absence of spongiosis or acantholysis. Therapeutically, Dapsone is the first-line treatment in SPD [4, 5], and other treatment options are etretinate, acitretin, PUVA, narrow-band (TL-1) UVB phototherapy, and colchicine [6, 7]. 2. Case Report A 7-year-old boy was admitted to our clinic with a 3-week-old itchy eruption located on the trunk, on the limbs, and on the face. He had a history of atopic dermatitis, while his familiar anamnesis was negligible. A complete blood count and the studies of serum biochemistry showed normal results; moreover serum protein electrophoresis had negative results. The lesions initially developed on the trunk and