Urticaria pigmentosa (UP) is the most common form of cutaneous mastocytosis in children. It can be diagnosed clinically, based on the appearance of numerous brownish macules and papules that are symmetrically distributed, mostly on the trunk and the extremities. Skin biopsy is helpful in establishing the diagnosis. Treatment options generally include antihistamines and/or topical corticosteroids. In most cases, pediatric UP tends to disappear spontaneously before puberty. We present the case of a 9-month-old male with a history of multiple brownish patches and plaques, which started when he was four months old. He was diagnosed with UP based on clinical and histopathologic findings, and was prescribed oral antihistamines and emollients for symptomatic treatment.
cutaneous mastocytosis ; mast cell degranulation