What is a mast cell?

Mast cells are immune cells that are responsible for allergies. They live in the barrier tissues of your body, such as the respiratory tract, the gastrointestinal tract, and the skin. They may react to allergens, medications, infections, or venoms. Allergens are anything that can trigger allergies - trees, grass, dust, animals, etc. When mast cells become activated, they release chemicals (histamine, tryptase, and others) that start an inflammatory response. When they do their job properly, mast cells defend the body and promote wound healing.

What is Mast Cell Activation Syndrome (MCAS)?

Mast cell activation syndrome (MCAS) results when mast cells become over-reactive to environmental triggers. This can cause symptoms in the skin (hives, flushing, itching), gastrointestinal tract (abdominal pain, cramping, bloating, nausea, vomiting, diarrhea), or respiratory tract (shortness of breath, nasal congestion) - the places where mast cells live. The inflammatory mediators released by mast cells into the blood stream may also lead to low blood pressure, lightheadedness, fatigue, brain fog, or anaphylaxis (severe, life threatening allergic reaction).

Officially, the diagnosis of MCAS requires 3 components: (1) symptoms in 2 or more organ systems, (2) improvement in symptoms with histamine blocker or mast cell stabilizer treatment, and (3) laboratory studies showing elevated MCAS mediators, such as tryptase. In practice, the third criteria is hard to accomplish. Approximately 5% of the general population has extra copies of the alpha-tryptase gene, leading to elevated tryptase levels at baseline. Accurately diagnosing MCAS through tryptase levels would require precise timing with a blood draw 30-120 minutes after a flare, and then a baseline level drawn when not having a flare. In practice, many experts will treat a patient if they suspect MCAS, even without confirmatory lab results.

Could I have MCAS?

If you are suffering with hives, itching, food intolerance, bloating, nausea, diarrhea, sinus congestion, shortness of breath, lightheadedness, fatigue, brain fog and suspect you may have mast cell disease, schedule an appointment with Dr. Jennifer Tang, for evaluation and treatment in California.