Mastocytosis.

Mastocytosis is a rare disease caused by excessive production of mast cells. Clinical presentation is variable, often based on the type of mastocytosis, but in all types of mastocytosis there seems to be an increase in the risk of anaphylaxis. Systemic mastocytosis is diagnosed based on bone marrow biopsy. Treatment is variable based on the type of mastocytosis, but trigger avoidance and anaphylaxis treatment are mainstays. There are no therapies that change the natural course of mastocytosis. For cutaneous mastocytosis, treatment is conservative and aimed at symptom relief.