If you’ve been searching for solutions to your mysterious health symptoms, they could be caused by Mast Cell Activation Syndrome.
Mast cell activation syndrome (MCAS) is an immunological condition where mast cells inappropriately secrete mast cell mediators. Mediators include but are not limited to histamine, which can cause widespread and chronic inflammation.
This mediator release can be excessive and/or chronic and result in long-lasting symptoms in almost any cell of the body where their receptors are found. This can potentially affect every organ system in the body.
Some experts believe as many as 14 to 17 percent of the US population have MCAS, which is one out of every six to seven people. It’s also been estimated to take up to 10 years to reach a MCAS diagnosis. This is mostly due to the lack of awareness surrounding MCAS.
Because mast cell activation syndrome goes unnoticed for years, I’d like to dig a bit deeper and uncover some of the symptoms and lab work available that can help with MCAS diagnosis.
Symptoms of MCAS
Patients who have MCAS typically have been struggling with inflammation-related symptoms over the years, which commonly include:
- Having allergies as a toddler
- Various rashes that came and went
- Gut conditions (that may have been misdiagnosed)
- Poor wound healing
While these are common MCAS symptoms due to mast cell mediators occurring throughout the body, a person can be affected by symptoms that are more widespread. These can include, but are not limited to:
- Feeling as though you’ve always been sick
- Overreaction to bee stings and mosquito bites
- Shortness of breath
- Feeling lightheaded when you stand
- Ringing of the ears
- Facial and chest flushing
- Frequent colds, infections or fevers
- Food, chemical, and drug sensitivities and intolerances
- Heat intolerance
You can also find a comprehensive list of MCAS symptoms in my in-depth article, Mast Cell Activation Syndrome and Histamine: When Your Immune System Runs Rampant.
You have the option to get testing done with a doctor to help confirm the MCAS diagnosis. I recommend you have these tests done with a doctor who’s experienced in MCAS because it’s still largely unknown, even in the medical community.
Lab work for MCAS
Working with a doctor who specializes in MCAS is your best bet as you’ll need to get testing on multiple occasions since the symptoms of MCAS wax and wane. False negatives are a common occurrence with MCAS testing. In fact, positive lab work is only obtained 20 percent of the time. However, testing can still give you a lot of valuable information regarding your mast cell mediator status. Testing for MCAS is quite complex and requires specialized handling of tissue samples.
The most important tests are:
- Histamine – plasma – Quest 36586 – must be chilled. Normal range – 28-51 ug/l.
- N-Methylhistamine – 24-hour urine – must be chilled. Normal range – less than 200 mcg/g.
- Prostaglandin D2 – plasma – must be immediately chilled and spun in a refrigerated centrifuge. Must be off NSAIDS (Motrin, Advil), aspirin, ASA, anything containing aspirin, for 5 days.
- Prostaglandin D2 (PGD2) – 24-hour urine – specimen collection must be chilled. Must be off NSAIDS (Motrin, Advil), aspirin, ASA, anything containing aspirin, for 5 days.
- Chromogranin A – Quest 16379 – must be off proton pump inhibitors (PPIs) and H2 blockers (Pepcid and Zantac) for 5 days before tests, since they can falsely elevate chromogranin A.
There are others you can have taken, which you can find in more detail in my in-depth article, Mast Cell Activation Syndrome and Histamine: When Your Immune System Runs Rampant.
More information regarding a low-histamine diet may found found in my guide here.
Dr. Bruce Hoffman, MSc, MBChB, FAARM, IFMCP is a Calgary-based Integrative and Functional medicine practitioner. He is the medical director at the Hoffman Centre for Integrative Medicine and The Brain Centre of Alberta specializing in complex medical conditions. He was born in South Africa and obtained his medical degree from the University of Cape Town. He is a certified Functional Medicine Practitioner (IFM), is board certified with a fellowship in anti-aging (hormones) and regenerative medicine (A4M), a certified Shoemaker Mold Treatment Protocol Practitioner (CIRS) and ILADS trained in the treatment of Lyme disease and co-infections. He is the co-author of a recent paper published by Dr. Afrin’s group: Diagnosis of mast cell activation syndrome: a global “consensus-2”. Read more about Dr. Bruce Hoffman.