A case of bullous pemphigoid in infancy treated with local corticosteroids.

Bullous pemphigoid (BP) is an immune-mediated subepidermal vesiculobullous eruption, whose true incidence is unknown, but it is considered extremely rare in children, with a usually indolent course and rare relapses. Diagnosis is often belated, because of the invasive assessment with biopsy for typical immune-pathologic findings to differentiate it from Dermatitis Herpetiformis and Linear IgA bullous dermatosis (LABD), more common in children. A 4-year-old girl presented with one year history of erythematous-edematous and erythematous-bullous eruptions on the genitalia, periocular regions, dorsal and palmo-plantar surfaces. At onset erosions of the month and lips where considered a primary herpes simplex infection from the pediatrician, but repeated courses of systemic antivirals were completely ineffective, while application of a antibiotic-steroidal cream was of partial benefit. Histopathology showed a dermo-epidermal blistering, with a marked eosinophilic infiltrate. Direct immunofluorescence showed a characteristic positive linear IgG and C3 band at the basement membrane zone (BMZ). Complete hematic-chemical and instrumental examinations gave normal results, excluding associated pathologies. Due to paucity of lesions and good response to local treatment with moderate potency cortisones, in agreement with the parents, no systemic therapy was started. No recurrence occurred in the 2 year follow-up after complete remission. The case is reported for the rarity of the childhood form, and the importance of the differential diagnosis for management and treatment. Good response to topical treatment is stressed, avoiding the risks of long-term systemic drug administration.