The MastAttack 107: The Layperson’s Guide to Understanding Mast Cell Diseases, Part 29

37. What is the difference between mast cell activation syndrome, mast cell activation disorder, and mast cell activation disease?

Mast cell activation syndrome refers to a condition associated with very specific symptoms associated with mast cell mediator release. There are multiple sets of criteria for diagnosing mast cell activation syndrome so it is hard to be more specific than this. Generally, patients with MCAS have mast cell symptoms, evidence of mast cell activation seen in urine or blood tests, and response to medications that manage symptoms seen with mast cell activation. Several variations of mast cell activation syndrome now have ICD-10 codes, an important step towards becoming more accepted diagnoses.

Mast cell activation disorder is usually used interchangeably with mast cell activation syndrome. However, when pluralized as mast cell activation disorders, it sometimes refers broadly to any disease characterized by mast cell activation, like mast cell activation syndrome and systemic mastocytosis.

Mast cell activation disease is a broad term used for any disease characterized by mast cell activation, like mast cell activation syndrome and systemic mastocytosis.