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    Created in 2008, Phoenix Rising is the largest and oldest forum dedicated to furthering the understanding of and finding treatments for complex chronic illnesses such as chronic fatigue syndrome (ME/CFS), fibromyalgia (FM), long COVID, postural orthostatic tachycardia syndrome (POTS), mast cell activation syndrome (MCAS), and allied diseases.

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Poll: Does your ME/CFS include MCAS?

I have ME/CFS and....

  • I also have MCAS (Mast Cell Activation Syndrome)

    Votes: 22 43.1%
  • I do not have MCAS (Mast Cell Activation Syndrome)

    Votes: 29 56.9%

  • Total voters
    51
Messages
54
I suffer from terrible mast cell issues along with my ME/CFS. Smokes, Molds, Fragrances, and chemicals from new products like furniture, clothing, and general merchandise all set me off terribly. I was under the impression that this was true for the majority of ME/CFS sufferers, but another patient has caused me to doubt this. I hope you'll participate in this poll so we can see how prevalent MCAS is among those with ME/CFS.
 
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Snowdrop

Rebel without a biscuit
Messages
2,933
What you are describing sounds more like Multiple Chemical Sensitivity than Mast Cell Activation Syndrome.

And while I suspect it is different for others I do have mild MCAS which has developed over time. I had been mildly ill with ME for decades and the MCAS developed as I got more ill.
 

ryan31337

Senior Member
Messages
664
Location
South East, England
What you are describing sounds more like Multiple Chemical Sensitivity than Mast Cell Activation Syndrome.
Having spent some time around MCAS communities recently I've seen quite a few people with solid MCAS diagnosis reliably experience reactions (typically anaphylaxis) from fragrances and chemicals - it can very much be an MCAS thing.

I've been under suspicion for MCAS but I'm lucky to be far more mild. I have the basic common stuff like
pruritus, dyshidrotic eczema, bloating & stomach pain when I react, though usually only to something ingested. On occasion it will progress to diarrhoea & blood pressure swings, which I guess could be argued as low level ana.

I'm of the opinion mine is more related to mast cell provocation from POTS and SIBO, rather than a 'true' MCAS, whatever that is!
 
Messages
54
What you are describing sounds more like Multiple Chemical Sensitivity than Mast Cell Activation Syndrome.

And while I suspect it is different for others I do have mild MCAS which has developed over time. I had been mildly ill with ME for decades and the MCAS developed as I got more ill.

How do you differentiate between MCAS and MCS? I see the two terms as synonymous. If MCS isn't mast cell mediated i'm not sure what else would explain it.
 

Snowdrop

Rebel without a biscuit
Messages
2,933
How do you differentiate between MCAS and MCS? I see the two terms as synonymous. If MCS isn't mast cell mediated i'm not sure what else would explain it.

I actually don't know what the difference is between MCS and MCAS. From reading here on PR your post sounded more like what is described as MCS. I'd be interested to know the difference from anyone who knows the difference.

Just as information--I have a heightened sense of smell and many smells annoy me if strong but I don't think this is what is meant by MCS. I also have a heightened sense of hearing so I think of it that way. My MCAS is a growing list of allergies for which I need to take antihistamines etc.

But as I said I'd like to understand the difference too.
 

Skippa

Anti-BS
Messages
841
I always suspect something along these lines, in a mild way (some triggers are a pain but others seem fine), but I don't have a diagnosis and it's not bad enough to seek one.

So I'll abstain,
 

junkcrap50

Senior Member
Messages
1,330
I encourage everyone to read Dr. Afrin's book Never Bet Against Occam: The Chronic Illness Connection?. He is the expert on MCAS in the US. He believes 10-17% of all Americans have some degree or type of MCAS. He presents a lot of evidence that MCAS's symptoms are much wide ranging than the typical highly reactive and high sensitivity to fragrances, chemicals, medications, etc (typical triggers). Many symptoms you wouldn't think would be related to MCAS have gone away after he successfully applied MCAS treatments. He really opened my eyes about the topic and I now believe that MCAS has an important role in CFS.

EDIT: Fixed book title
 
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Hip

Senior Member
Messages
17,824
How do you differentiate between MCAS and MCS? I see the two terms as synonymous. If MCS isn't mast cell mediated i'm not sure what else would explain it.

MCAS and MCS are two distinct conditions.

The Wikipedia MCS page does not mention MCAS, and the Wikipedia MCAS page does not mention MCS.

The comprehensive list of proposed physical mechanisms (and the discounted psychological mechanisms) for MCS provided by James Madison University does not mention MCAS.

Nobody knows what causes MCS for sure, but there are many theories. Whereas the cause and mechanism for MCAS is known.


To have MCAS, you would probably satisfy the proposed diagnostic criteria for MCAS, which are the following:
Proposed criteria for the diagnosis of mast cell activation syndrome
  1. Episodic symptoms consistent with mast cell mediator release affecting two or more organ systems evidenced as follows:
    1. Skin: urticaria, angioedema, flushing
    2. Gastrointestinal: nausea, vomiting, diarrhea, abdominal cramping
    3. Cardiovascular: hypotensive syncope or near syncope, tachycardia
    4. Respiratory: wheezing
    5. Naso-ocular: conjunctival injection, pruritus, nasal stuffiness
  2. A decrease in the frequency or severity; or resolution of symptoms with anti-mediator therapy: H1 and H2 histamine receptor antagonists, anti-leukotriene medications (cysLT receptor blockers or 5-LO inhibitor), or mast cell stabilizers (cromolyn sodium)
  3. Evidence of an elevation in a validated urinary or serum marker of mast cell activation: Documentation of elevation of the marker above the patient’s baseline during a symptomatic period on at least two occasions; or if baseline tryptase levels are persistently >15ng, documentation of elevation of the tryptase above baseline on one occasion. Total serum tryptase is recommended as the markers of choice; less specific (also from basophils) 24 hour urine histamine metabolites, or 11-beta-prostaglandin F2.
  4. Primary (clonal) and secondary disorders of mast cell activation ruled out (Table I).
Source: Table II of the paper: Mast Cell Activation Syndrome: Proposed Diagnostic Criteria