Maculopapular cutaneous mastocytosis (also known as urticaria pigmentosa) is a common form of cutaneous mastocytosis characterized by brown patches or freckles on the skin that result from an abnormal collection of mast cells. The skin may be very itchy and rubbing may lead to hive-like bumps or fluid-filled blisters. The condition is most common in children, but adults can also be affected. Treatment may include antihistamines, topical steroids, and/or phototherapy. Over time, the mastocytosis in younger patients usually becomes less itchy and the skin patches tend to improve. In adults, systemic mastocytosis may develop.

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Maculopapular cutaneous mastocytosis is generally not serious and many cases do not require treatment. For those cases that do, oral antihistamines, topical steroids, and a photochemotherapy called PUVA may be used. These treatments are aimed at reducing the symptoms of the condition and making patients more comfortable.

The prognosis for children with maculopapular cutaneous mastocytosis is good. Up to 50% of cases improve and 30% of cases resolve completely by adolescence.