Mast cell activation syndrome
The underlying pathophysiology of MCAS involves excessive systemic activation of mast cells, leading to degranulation and release of vasoactive mediators such as histamine and tryptase. These mediators cause an array of symptoms and signs including flushing, pruritus, urticaria and angioedema, nasal congestion and pruritus, bronchoconstriction and throat swelling, headache, and diarrhea. A severe complication of MCAS is systemic anaphylaxis. The disease is often episodic in nature, with symptoms waxing and waning over time. MCAS is most commonly found in White females. Symptoms often start in childhood and continue into adulthood if left untreated.
D89.40 – Mast cell activation, unspecified
16697871000119100 – Mast cell activation syndrome
Differential Diagnosis & Pitfalls
Drug Reaction Data