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Mast Cell Activation Syndrome

What is Mast Cell Activation Syndrome? “Mast cell activation syndrome (MCAS), is an immunological condition in which mast cells mistakenly release too many chemical mediators, resulting in several chronic symptoms involving the skin, gastrointestinal tract, heart, respiratory, and neurologic systems. Mast cells are present throughout most of our bodies and secrete different chemicals during allergic reactions. Symptoms include episodes of abdominal pain, cramping, diarrhea, flushing, itching, wheezing, coughing, lightheadedness and potential problems with “brain fog” or other difficulties with memory. The cause of MCAS is unknown. Treatment includes several combinations of medications like antihistamines and mast cell stabilizers.” (from the Genetic and Rare Disease Information Center)

What Does MCAS Look like for Me? I always assumed I had allergies – I’m sensitive to EVERYTHING, especially fragrances – and I’ve always had various symptoms I thought were allergies, but in my 20s I was tested and it was negative for everything. Some of these symptoms have been attributed to my EDS, POTS, or gastroparesis, and some of them it’s impossible to tell which condition is causing them. The main symptoms (not a complete list) that I attribute to my mast cell disorder are:

  • Skin symptoms – Super dry, sensitive skin – random rashes, hives, bruising,  Dermatographism, contact/pressure rash, flaking finger and toenails, and red marks/rash/hives/flushing from: medical adhesive (hives), cosmetics, chemicals, contact, heat, cold, showering, sun, etc.
  • Allergy-like symptoms with negative allergy testing – generally chronically irritated nose, eyes, mouth, and throat, sinus pain, swollen nasal passages, congestion/runny nose, itchiness, rashes, flushing, headaches, “allergic shiners,” red, burning, itchy eyes, swelling of lips, mouth, tongue, and severe attacks where all of those symptoms come on at once, suddenly
  • Burning Mouth Syndrome – this can be so severe I can’t talk or drink. It can be debilitating, if it’s bad enough all I want to do is lie down alone. Tongue, gums, lips, throat and jaw. I can’t overstate how painful and upsetting this is. Salt and acid exacerbate it, but it also happens randomly. My mouth has some degree of pain much of the time. No doctor, including a ear, nose and throat specialist and my dentist, could explain it, until I got the MCAS diagnosis and found out that it’s a fairly common MCAS symptom. I also get sores on my lips and sometimes if I’m having an attack the skin on my lips just sloughs off. Not pretty.
  • Pain – bone pain (this is unbelievably painful), muscle pain, and pain at my stoma (I attribute most of my joint pain and muscle pain to my EDS, the MCAS pain is specific and different)
  • GI problems – I have gastroparesis and colonic inertia, which are attributed to my EDS. As my baseline, I have to be careful to keep up with my bowel regimen for my constipation, and I almost always have some degree of GI discomfort. For the past year I’ve been trying to introduce food, up to 4 tbsp per day, but last fall I suddenly started reacting to the few foods I was eating. I get attacks of cramps, gas, alternating constipation and diarrhea, severe, painful bloating, and nausea.
  • Major cognitive dysfunction – brain fog, confusion, word recall issues, troubling completing sentences, completely forgetting what I was talking about mid-sentence and being unable to remember, memory problems, trouble focusing, etc. There’s no doubt this is also caused by my dysautonomia/POTS, but cognitive dysfunction is a major symptom in my severe mast cell attacks and part of my baseline.
  • Episodes of extreme fatigue and malaise – I always have some degree of fatigue. Fatigue, for me, is different from just being tired. It’s not sleepiness. It’s like working a long day in the hot sun on two hours sleep, except I wake up feeling like that. It makes me feel like I’m slogging through the day, wading through mud, dragging my body around the house. During my mast attacks, I am so fatigued and weak that I can barely sit up on the couch. Malaise actually means a feeling of general discomfort, like something isn’t right. It’s a really strange feeling for me, and it signals a severe attack. Before hearing the definition of malaise, I’d say “it feels like something is wrong, like my body is fighting itself, or is in shock.”
  • Previous respiratory symptoms – I had exercise induced asthma which went away in my teens. I also had chronic bronchitis every winter since my teens that finally went away when I had to stop working.

I had blood and patch allergy testing in 2012 and it all came up negative, which I was extremely surprised about because my entire life I assumed I had allergies, seasonal and otherwise. The reason I had testing was because I had started to react to alcohol and fragrances and was getting a lot of rashes.

I’m working on updating this page with more information on MCAS. It’s still a recent diagnosis for me, so I keep learning more about it and how it affects me. In the meantime, read more about Mast Cell Activation Disorder (the umbrella term that encompasses Mastocytosis and Mast Cell Activation Syndrome) at Mast Attack, a great website by a scientist who has systemic mastocytosis. I’m not affiliated with her, just think it’s the best resource I’ve found on the subject, aside from Dr. Lawrence Afrin’s book, Don’t Bet Against Occam (if you have MCAS, read it! It’s worth it!).