Mast Cell Activation Syndrome

**Definition:** A clinically and genetically heterogeneous group of mast cell disorders in which there is aberrant release of mast cell mediators with little to no accompanying proliferation of MAST CELLS.

**Tree numbers:** - C20.762.500

**Synonyms:** - Mast Cell Activation Syndromes - Idiopathic Mast Cell Activation Disorder - Non-Clonal Mast Cell Activation Syndrome - Nonclonal Mast Cell Activation Syndrome - nc-MCAS - Non-Clonal Mast Cell Activation Disorder