Risk of anaphylaxis in adult patients with systemic mastocytosis preceded by urticaria pigmentosa. Report of three cases

Mastocytosis is a heterogeneous group of rare disorders characterized by abnormal proliferation and tissue infiltration with activated mast cells. Indolent systemic mastocytosis (ISM) is the most frequent form in adults, sometimes preceded by cutaneous involvement called urticaria pigmentosa. Patients with ISM have an increased risk of anaphylaxis induced by a broad range of allergic or non-allergic triggers. We report three cases of patients diagnosed with urticaria pigmentosa for many years, addressed to our hospital for allergist and hematologist consultation, due to progressively and severe systemic manifestations.