Mastocytoma with late blisters.

Abstract

Mastocytoma means one (or more up to a conventional maximum of 5) infiltrated skin lesion consisting of mast cells. Case studies that include adults talk about a frequency of 4% (2) among the cases of mastocytosis, while in the infantile case studies its frequency reaches 46% (1). Mastocytoma usually begins early, in the first months, with a patch that becomes erythematous brown and infiltrated and undergoes episodes of local and generalized histamine release more frequently than urticaria pigmentosa. These episodes become less frequent and severe after the first year of life and their progressive decrease is an expression of spontaneous regression of mastocytoma. Sometimes mastocytoma can reach the observation for the first time in the blistering phase, creating problems of differential diagnosis with other bullous skin disorders. In the case of diagnostic doubt Darier's sign is diriment.