Parasite Infections: The Mast Cell Activation connection

parasite infections and mast cell activation histamine intolerance

If you’ve been following these articles for some time you’ll know that I write about Blastocystis infections quite frequently

It isn’t a coincidence. I contracted this unpleasant bug a few years back and have tried a range of treatments from straight up antibiotics to multiple herbal antimicrobials protocols.

For some reason, and I know I’m not alone, certain Blastocystis infections are very recalcitrant and difficult to treat (4).  Let’s not leave out the Dientamoeba infection either. For me these two bugs have been impossible to clear.

I must say that the herbal antimicrobial protocols helped considerably. Containing a whole range of herbs including

After the herbal protocols I felt immensely better. So much so that I assumed I was clear and free of the parasite infections. Lo and behold, minor gut symptoms returned, mainly bloating after food. This is a good place to mention the essential importance of retesting after a treatment. If I had never retested I would still think that the bizarre and seemingly unrelated symptoms have nothing to do with Blastocystis hominis infection.

Update – After years of trying different herbal antimicrobial approaches I have managed to clear the two parasite infections and have learned a ton about the different herbs that work, which ones may negatively impact your beneficial gut flora and have formed some ideas on how long to take herbal medicine to get the best results.

Mast Cells

This brings me to the subject of this article. Mast cell activation in the presence of a gastrointestinal infection. When I first heard about mast cells and histamine intolerance my eyes glazed over and I lost interest in the white paper I was reading. Fast forward a year and I have certain unexplainable symptoms such as

  • Chronic sore throat
  • Sore lymph nodes just under my ears
  • Headaches
  • Fatigue and exhaustion
  • Bizzare food intolerances (more on that later)
  • Chronic sinusitis

Seeing as I didn’t have any gut symptoms I didn’t relate the upper respiratory tract issues with my gut infections. Then I heard a story from a practitioner friend who was treating a patient with the exact same symptoms plus a Blastocystis and Dientamoeba infection. So I decided to hit the literature and see what connections there might be.

Mast Cell Function

First off it is important to note that mast cells aren’t the problem here. One paper notes the beneficial immune functions these cells play in the human body that help maintain homeostasis including

  • Tissue repair
  • Angiogenesis
  • Innate immune function
  • Adaptive Immune function
  • Immune tolerance
  • Mediators of inflammation

“The strategic positioning of MCs at the interface between the host and the external environment near blood, lymphatic vessels, nerve fibers and a range of immune cells, including epithelial and dendritic cells, allows them to act as sentinels of invading microbes and respond rapidly to any change in environment by communicating with different immune cells” (7).

They have been described as sentinels, ready to deal with whatever comes their way. Definitely helpful allies but problematic when we keep triggering them into action.

mast cell activation parasite infection blastocystis dientamoeba byron bay gut health gut infection parasite

Image taken from Mast CellsPhenotypic Features, Biological Functions and Role in Immunity

In the picture above we can see that upon activation mast cells degranulate. This process involves the release of a whole range of different molecules including

  • Histamine – possibly the most important in our discussion
  • Cytokines – these are messenger molecules that can be pro-inflammatory or anti-inflammatory depending on their specific makeup
  • TNF – an inflammatory cytokine
  • Interleukins – 4,6 and 15 – yet another set of cytokine messenger molecules

Mast Cell Activation

How are these cells activated?

In the Fundamentals of Inflammation Joshua Boyce describes mast cells as a front line defence mechanism. As mast cells reside close to external environments such as the skin the airways and the gastrointestinal tract they are perfectly positioned to deal with incoming problems and degranulate, or release the contents listed above, in a range of different scenarios

  • IgE based allergies – proper allergic reactions that involve type 1 hypersensitivity. The most severe type 1 hypersensitivity is anaphylaxis
  • Pathogens
  • States of inflammation – an example here would be mucosal injury

While the first example of IgE based activation of mast cells is well understood and known for quite some time, the last two examples are worth more attention. Mast cell activation occurs from parasite infections (Blastocystis, Dientamoeba) and bacterial dysbiosis (Helicobacter, Klebsiella) as well as injured intestinal mucosa which is a consequence of such infections.

The resulting symptoms can be wide ranging and seemingly unconnected to a gut infection.

My symptoms included upper respiratory tract inflammation, headaches and extreme food sensitivities to histamine rich foods. Other symptoms of mast cell activation can include chronic/recurrent 

  • Flushing
  • Pruritus
  • Urticaria
  • Angioedema
  • nasal congestion 
  • Wheezing
  • throat swelling
  • Headache
  • Hypotension
  • Diarrhea

The list of symptoms comes from a review entitled Mast Cell Activation Disease and Microbiotic Interactions. The authors included an important point that all other disorders that could account for these symptoms need to be ruled out.

Take Home Points

Coming back to my personal experience I noted after a year or so of chronic Blastocystis and Dientamoeba infection there was a shift in symptoms from gut related (bloating, stomach ache, loose stools) to upper respiratory tract (chronic sinusitis aka blocked sinuses, sore throat, sore lymph nodes) all triggered from different foods. Cutting back on high histamine foods (coffee was particularly hard) has helped relieve the symptoms considerably but they aren’t gone by any means.

The link between mast cell activation and parasite infections is starting to be explored in the scientific literature (12,13,14,15,16). Understanding that many extra-intestinal symptoms may lead back to a gut infection is a key learning.

Proper gut testing is essential.

Are you suffering from symptoms that may be from mast cell activation? Leave a comment below.  

References and Resources

  1. Blastocystis hominis – A Protozoan Gut Parasite
  2. Blastocystis homminis – Probiotic Treatment
  3. Blastocystis hominis – Skin Disorders and Gut Infections
  4. Treatment failure in patients with chronic Blastocystis infection
  5. Stool Testing – My Personal GI Results CDSA + PCR
  6. Mast Cells and Anaphylaxis
  7. Mast CellsPhenotypic Features, Biological Functions and Role in Immunity
  8. Fundamentals of Inflammation
  9. Helicobacter Pylori – A Notoriously Popular Bacteria
  10. Klebsiella – Bacterial Dysbiosis, Detection and Treatment
  11. Mast Cell Activation Disease and Microbiotic Interactions
  12. IgE and mast cells in host defense against parasites and venoms
  13. Mast cells in allergy and infection: Versatile effector and regulatory cells in innate and acquired immunity
  14. Mast Cells in Gastrointestinal Disease
  15. The Role of Mast Cells in the Defence against Pathogens
  16. The Roles of Mast Cells in Parasitic Protozoan infections
  17. Recommended GI testing – CDSA + PCR
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  1. After losing a lot of weight almost 2 years ago after a heap of testing nothing was noted. But accompanying the weight loss was rashes around the eyes headache, fatigue and the feeling of tightness in neck. As well as irregular heart beat and all the other lovely stuff.

    After being plagued on and off and not feeling right for almost a year and a half slowly gained some weight back then was hit again with the same problems more testing to eventually confirm Dientamoeba.

    Haven’t explored antibiotics yet, doctor seems reluctant but life is miserable like this, and now depending on what I eat the symptoms of histamine intolerance get worse.

  2. Hi I’ve had blasto for 6 years and haven’t been able to test it with antibiotics successfully. I don’t eat gluten, dairy or sugar. But I do eat carbs, otherwise I’d be too weak. I’ve been diagnosed with MCA and POTS. However I beleive my gut infection is the root of all this. What was your protocol and how long did it take you. I feel I really need to get rid of this to be well again. Any advice would be a big help.

  3. Hello Todd,

    Thanks for sharing this article.I am happy that you resolved your issue. I was also tested positive with blastocytis and immensely sensitive to histamine containing and releasing foods.

    Would you elaborate your herbal antibiotic approach a little ?
    which of the herbal choices contributed most to your healing ?

    1. hey kaan, I have covered some of the herbs that helped shift my gut health back into balance here

      I’m not 100% positive that blastocystis is the issue in most people that have it. I think because it is easy to find on a cheap stool test that we blame it for other, harder to find, gut conditions. Things like SIBO, food intolerances and allergies and even large bowel dysbiosis should be on your radar, especially if you are struggling with histamine reactivity. The good thing is that all of the herbs that we use to treat blastocystis can help resolve bacterial overgrowth problems too.

    2. Every thing sound like the problems I’ve had for years. Taking years even to realize parisite’s was a issue. Treatment for them is never ending and I wonder how I’m even alive. Now the skin, the itch the crawl. The over growth in cells, callucus, thickening, cracking, sores and scares. Light, smell, a touch can drive you mad. Dizzy, disoriented, weak pain, electrical buzz, shooting pain, rolling pain, eyes, ears ,throat, joints burn, knots and tumor like bumps like rocks on ankles knees hips shoulders. Jaw and face pain. I could go on and on.

  4. I have been dealing with fatigue, heart palpitations, Anxiety, new extreme food sensitivities, asthma like symptoms, and there’s probably more, for the last five+ years. I have tried to treat for Lyme disease in the past with an iffy test, but couldn’t tolerate treatments. I was diagnosed through a stool test with klebsiella pneumonia, and treated that with biosidin and grapefruit seed extract. I felt better for a while. I also had a cavitation surgery on my old wisdom teeth sites, and they tested and said I had some sort of entomoeba parasite there. I’m wondering if all my symptoms could be from these parasites and disbiotic bacteria? What tests do you recommend to see if these things you mentioned are an issue for me? I live in the USA. And what type of dr could help me with this? A GI doctor?

    1. I forgot to mention that I am currently being treated for mast cell activation syndrome with antihistamines and mast cell stabilizers. It is helping, but I know not the cure. I’m trying to figure out what is triggering my mast cells.

      1. Hey Becky.

        It sounds like there may be a number of things contributing to your mast cell activation symptoms. The best approach, especially for chronic conditions, is to get to the bottom of what is triggering this response (often not as easy as it sounds). Lyme testing isn’t the greatest at the moment, and the entamoeba parasite results probably need attention too! Dysbiosis is best assessed with a microbiome stool test. I have been recommending Thryve to my patients now that Ubiome is out of business.

  5. Hi Todd,
    My symptoms seem to be related to many things – I was treated for acute Lyme over 20 years ago. In 2014 after a few years of searching for reasons for nerve irritation, numbing, pain, brain fog, and a host of other issues including bloating, constipation, endometriosis, fibroids…and the list goes on, I regretfully began antibiotic treatment for chronic Lyme/ Bartonella and other co-infections. I have been on an antibiotic rollercoaster for over 6 years and my body is a wreck. Symptoms can be related to a messed up gut, mast cell (swollen nasal passages, throat, white tongue (not yeast), nerve irritation. Not sure if you treat patients in the U.S., if not, any connections in the New York area?

    1. Hi Karalyn, thanks for sharing your experience. Unfortunately no I can’t take on patients in the USA and I don’t have a great referral either. So sorry I couldn’t be more help!

      1. Hi I same I cfs
        But love to some your herbs
        I recently got diagnosed with
        Blastocystis but I had for 5 years or more
        So these little shits are to rid of
        So I wonder how much costs?

  6. Hi I same I cfs
    But love to some your herbs
    I recently got diagnosed with
    Blastocystis but I had for 5 years or more
    So these little shits are to rid of
    So I wonder how much costs?

  7. This is a really interesting article, thankyou.
    I have been suffering with face flushing,angiodema, racing heart, tinnitus and oral food allergies for 18 months. An immunologist said it is Salicylate sensitivity but a low Sal diet hasn’t fixed it. A local naturopath said to get tested for Blasto and it as well as dientamoeba is positive. I have an appointment with her this week. Yours is the first internet article I have managed to find about this. Thanks once again.

  8. Wow…thamks for the article, O 4elate so much…I have mast cell activation syndroms and believe its a fut issue too, based on research heavy met asl toxicity asnd ch e mic a l toxicity too. Would you recommend coffee enemas as part of your herb healing protocol, Ive read much about them, but havent tried yet. Curious if this was also s part of your healing.

  9. My daughter (age 15) has been dealing with anaphylaxis and other similar symptoms that suddenly began 1yr ago (post COVID infection). She’s been seen by at least 5 pediatric specialists & diagnosed w/ Systemic Mastocytosis but no medication has helped her condition. After a ton of research on my own I have suspected parasites. With all of the information I have gathered, I’m not sure why all of her doctors have not ever suspected or tried to test for parasitic infection. I am currently waiting on a black walnut, wormwood and clove tincture to come in the mail and just came across your article on this subject. Its been a very difficult year for my daughter and I am hoping that herbal medicine will heal her body. She’s suffered with GERD since birth, gut issues in general but why do so many medical professionals overlook the possibility of parasites causing so many gut issues.

    1. Hi Beth, thanks for taking the time to share your experience. I would push for some functional testing to get to the bottom of your daughters chronic illness. I have found the OAT test to be a great place to start. Parasites could be an issue (a good quality stool test should find them if they are there) but also mould exposure can trigger many histamine mediated conditions too.

    2. Hello Beth,

      I am also experiencing sudden anaphylaxis post-COVID. Skin prick test did not reveal allergies. The only thing that has helped is a very restrive, low-histamine diet. Has your daughter’s condition improved since?

      1. I should also mention that I did a stool test, which did not find any parasites. However, they did find extremely high levels of the bacteria morganella. This bacteria is linked to histamine production. Grapefruit seed extract was one recommendation but I have yet to try it due to fear of reaction.

  10. Thank you very much for the articles. They are very informative! I wanted to ask how long it took before you saw improvements in your food intolerances following treatment? Is this something that happens at the same time or do the intolerances take a while to go away after your gut is back to normal? Thank you.

    1. Pleasure! It varies from patient to patient depending on what is driving the intolerances. Sometimes it is leaky gut other times it is a co-factor deficiency (think nutrient/vitamins/minerals) leading to enzyme dysfunction. Treating the overgrowth or infection then healing and sealing the gut is the general approach. Nutrient repletion can be a total game changer for food intolerances.

      Hope that helps!

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