Mast Cell Activation Syndrome (MCAS)
[UPDATED JUNE 2022]
As early as the first century BC, the Roman poet and philosopher Lucretius (c. 99 BC – 55 BC) had noted that
“..what is food to one man is bitter poison to others....”
And it is fairly certain that he was refering to allergic, and possibly anaphylactic reactions. See Wikipedia link on Lucretius
But, this is another clinical picture which seems to be becoming increasingly common. It is important to realise that this is not a diagnosis but a clinical picture. A proper diagnosis gives us the mechanism of the clinical picture and that has obvious implications for management.
What is MCAS?
This occurs when the allergy and mast cells release mediators such as interleukins, histamine, leukotrienes, prostaglandin, heparin and enzymes such as tryptase. These can produce many symptoms.
The diagnosis is best made on clinical grounds and the clues are:
1- From the symptoms
|Mediators - any or all of these can be released in MCAS
|Possible symptoms associated with....
|Fatigue, weight loss, nausea, enlarged lymph nodes
|Anaphylaxis, flushing, itching, hives, sneezing, diarrhoea, hypotension
|Shortness of breath due to asthma
|Flushing, bone pain, brain fog, cramping
|Osteoporosis, skin lesions
|Osteoporosis, problems with clotting/bleeding
2- From the history
|Heat, cold or sudden temperature changes, weather changes. Sun/sunlight
|Mast cells are known to respond to several mechanical irritants – one example is cold urticaria
|Make them less irritant with Magnesium, Vitamin D, Vitamin C (in high doses this has an anti-histamine effect BUT it also kills microbes and so may produce a Herxheimer reaction)
|Mechanical irritation, friction, vibration
|Ditto above eg Dermographism
|Infections (viral, bacterial or fungal)
|MCAS is part of the natural defences against infection
|Identify and treat the infection
|Exercise, stress: emotional, physical including pain. Severe fatigue
|Immune system does not have the energy to respond appropriately
|Improve energy delivery mechanisms - See Overview of CFS/ME protocol including energy delivery mechanisms
|High carbohydrate diet
|Makes for a fermenting gut - see Fermentation in the gut and CFS
|PK diet and Vitamin C to bowel tolerance. See The Paleo Ketogenic Diet - this is a diet which we all should follow
|Alcohol, NSAIs, (Non-steroidal anti-inflammatory drugs) opioids
|Make for Leaky Gut
|Drugs, NSAIDs, and some local anaesthetics) and contrast dyes
|Destabilise cell membranes
|Foods, Pollen, pet dander, etc Venoms (bee, wasp, mixed vespids, spiders, fire ants, jelly fish, snakes, biting insects, such as flies, mosquitos and fleas, etc.)
At the first sign of any bite, apply topical Lugol’s iodine 15% to the bite. This gets rid of swelling and itch within seconds! In the garden I carry this with me at all times!
|See Diet, Detox and Die-off Reactions
|Natural odours, chemical odours, perfumes and scents. Pollution
|Multiple chemical sensitivity- - triggers degranulation probably by destabilising cell membranes
|See Chemical Poisoning and Multiple Chemical Sensitivity (MCS) - how to reduce your daily exposures , Multiple Chemical Sensitivity (MCS) - a common problem and often triggered by exposure to chemicals and Multiple Chemical Sensitivity (MCS) - Principles of Treatment
|Possibly electromagnetic pollution eg 4G, 5G
|We know this affects calcium influx and so destabilises cell membranes
|Poor hydration may be part of membrane destabilisation
|To be hydrated you need FAT and SALT and WATER
What are the mechanisms that produce Mast cell reactions?
|Gram negative bacteria such as E coli, pseudomonas, klebsiella, haemophilus influenzae, Citrobacter freundii, proteus, H pylori, Rickettsia and many others
Fungi and yeast - -S cerevisiae
|Many of these microbes can be seen in tests such as a Comprehensive Digestive Stool Analysis.
Some appear in probiotics
|Klebsiella, mycoplasma, pseudomonas
Fungi – aspergillus fumigatus
|May be picked up in sputum specimens.
Fungal infection often missed in sputum samples – urinary mycotoxins may be a helpful test. See Great Plains Lab Mycotoxin Test
|Consider if there is acute or chronic upper airways inflammation
|Depends on which virus!
MCAS is found in conjunction with Ehlers-Danlos Syndrome (EDS) and postural orthostatic tachycardia syndrome (POTS).
- EDS - there is poor quality connective tissue. If the connective tissue is poor then microbes start to leak through the gut wall and so leaky gut is more likely. See Leaky Gut Syndrome. Microbes come into greater contact with mast cells. MCAS may also be an appropriate reaction to these microbes trying to invade the body through the gut wall. Please see Ehlers Danlos Support UK charity website for more information.
- POTS - this results where there are poor energy delivery mechanisms and so the immune system is under-powered. The point here is that MCAS may be an entirely appropriate reaction to chronic infection. If the immune system is under-powered then the usual front line fighters of lymphocytes and neutrophils do not have the energy to fight and so other cells are recruited – these include mast cells. Please see POTS UK charity website for more information.
The link between MCAS and POTS can be seen below in diagrammatic form -
The above mechanisms give us a logical approach to treatment:
Sort out the fermenting gut
As you can see, many of the triggers of MCAS come from the gut. Whilst the lower gut copes with them fine (it is supposed to be full of fibre fermenting friendlies), the upper gut does not - indeed the upper gut is meant to be a pretty much sterile digesting gut. First put in place interventions to treat the upper fermenting gut of which the most important are to starve the little wretches out with a PK diet AND to kill them with vitamin C to bowel tolerance. See The Paleo Ketogenic Diet - this is a diet which we all should follow
Identify and treat any chronic infection
The starting point here is to improve the immune defences with Groundhog Chronic interventions. See Groundhog CHRONIC
We then may need specific treatments for tackle those little wretches who are so comfortably ensconced in the body that we need a nuclear weapon to dislodge them. This many involve antibiotics for bacteria, antifungals for fungi and antivirals for viruses. Much more information see my book “The Infection Game - life is an arms race"
Identify any other triggers and avoid
We know antibiotics can trigger an MCAS attack BUT it is possible this is a Herxheimer reaction – ie short term pain long term gain. See Diet, Detox and Die-off Reactions.
NSAIs, alcohol and opioids make Leaky Gut worse and so can worsen MCAS
Mop up histamine and other mediators in the gut
With clays such such as Toxaprevent 3 grams at night on an empty stomach taken away from food and supplements
Break histamine down in the gut with Diamine Oxidase enzyme
Sometimes helps - suggest DAO 4.2mgs taken 5 mins before food. Here is one such product - 'Seeking Health' - Histamine Block - 4.2mg
The figure of 4.2mg is suggested because most available studies used doses of 4.2 mg of DAO at a time up to 2–3 times daily just before meals. See HealthLine Article - Diamine Oxidase Supplements Explained and also this study:
Reprogramme the immune system
It may be that the MCAS has become switched on, has adequately dealt with the infection, but has not been switched off. In this event we need to put in places interventions to reduce useless inflammation such as high dose vitamin D (up to 10,000iu daily is completely safe, and if on a PK diet, with no dairy products, then up to 20,000iu daily is safe, but if you take more than that, then serum calcium needs to be monitored with blood tests), Low Dose Naltrexone and possibly micro-immunotherapy 2L ALLERG - see Reprogram the immune system with micro-immunotherapy
Interventions to improve energy delivery mechanisms
Interventions to improve the quality of connective tissue
Magnesium stabilises mast cells and so they degranulate more easily where there is a magnesium deficiency. Take Magnesium supplements - at least 300mgs of elemental Mg daily together with vitamin D as above (vitamin D is essential for the absorption of Mg)
CBD (Cannabidiol) Oil
Many people have found benefit from using CBD oil - please see this article - Medical Cannabis & Mast Cell Activation Syndrome.
Possibly use antihistamines, cromoglicate, quercetin and other such medications
I put this as a last resort because it is possible that MCAS is a vital defence to protect against infection and so using antihistamines and other such medications may be a case of symptom squashing. The interventions, as above, treat the mechanisms as identified, and are “sustainable” in that they reverse, not escalate, disease processes.
- Overview of CFS/ME protocol including energy delivery mechanisms
- Fermentation in the gut and CFS
- The Paleo Ketogenic Diet - this is a diet which we all should follow
- Chemical Poisoning and Multiple Chemical Sensitivity (MCS) - how to reduce your daily exposures
- Multiple Chemical Sensitivity (MCS) - a common problem and often triggered by exposure to chemicals
- Multiple Chemical Sensitivity (MCS) - Principles of Treatment
- Diet, Detox and Die-off Reactions
- Leaky Gut Syndrome
- Groundhog CHRONIC
- “The Infection Game - life is an arms race"
- Reprogram the immune system with micro-immunotherapy
- low Dose Naltrexone
- Diagnosis and Treatment of Chronic Fatigue Syndrome and Myalgic Encephalitis
- Wikipedia link on Lucretius
- Herxheimer reaction
- Diamine oxidase supplementation improves symptoms in patients with histamine intolerance
- 'Seeking Health' - Histamine Block - 4.2mg
- The GAPS diet
- Joint Mix
- Sunshine Salt
- Mast Cell Action charity website
- POTS UK charity website
- Ehlers Danlos Support UK charity website
- Medical Cannabis & Mast Cell Activation Syndrome.
Please see Mast Cell Action charity website for more information.
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