Mast Cell Disorders
Activation of mast cells that leads to undesirable symptoms is a mast cell disorder called mast cell activation syndrome (MCAS).30
Signs that you have MCAS would be presenting with typical clinical signs and symptoms of mast cell activation, an increase of mast cell mediators in biological fluids after an acute event, and a major response to mast cell targeting medications.
Typical symptoms of MCAS are:
- Flushing, itching, hives, or swelling of the skin
- Runny or itchy nose
- Wheezing or throat swelling
- Headache
- Drop in blood pressure
- Diarrhea
Different types of MCAS result from differences in disease manifestation. The production of too many mast cells is primary MCAS, the abnormal activation of mast cells from underlying diseases (such as allergy, autoimmune, or infectious) is secondary MCAS, and mast cell activation in the absence of clonal mast cell expansion and definite triggers is idiopathic MCAS.
Primary MCAS
Primary MCAS involves the production of too many mast cells and is often the result of a mutation of the KIT gene in mast cells, which leads to increased production and accumulation of mast cells in various tissues. Mastocytosis is a type of primary MCAS.
Common triggers of primary MCAS: 31
- Alcohol
- Skin irritation
- Spicy foods
- Exercise
- Insect stings
- Certain medications
Secondary MCAS
Secondary MCAS involves the activation of mast cells from underlying diseases (such as allergy, autoimmune, or infection).
Triggers of secondary MCAS: 32
- Food and environmental intolerance or allergies
- Autoimmune disorder
- Bacterial infection
People can have both primary and secondary MCAS, which essentially increases the number of bombs that are prone to detonate. This combination is dangerous and increases the likelihood of life-threatening anaphylaxis.
Idiopathic MCAS
If no clonal mast cell expansion or definite triggers for mast cell activation are identified, then idiopathic MCAS is the diagnosis. The search for the underlying cause of mast cell activation should continue.