Mast cell activation

This is my mystery story of misbehaving mast cells that finally has an answer.

I share this story because mast cell disorders typically go undiagnosed for many, many years.  I don’t know if I have technically have a mast cell disorder, but I hope telling my story will help someone who does.

When I began to have symptoms in response to food, medicine, and environmental triggers, I gradually realized that they seemed consistently related to histamine release. My doctor agreed to test me and we discovered that I had elevated serum tryptase, a marker for mast cell disorders.  At the time, I also had a mild elevation in serum histamine.  Even though I ate a radically low histamine diet, I still had a bit too much histamine floating around in my blood stream.

Histamine is released by mast cells in addition to many other chemical mediators that can cause inflammation, pain, and general havoc in the body.  An elevation in histamine would generally be associated with classic IgE allergies.  However, I have none – my IgE levels are stunningly perfect.

People with mast cell disorders respond to a wide range of triggers, which may include environmental chemicals, foods, temperature changes, medicine, smells, stress, viruses and fungi, and on and on.  This is not an IgE mediated response – the mast cells are triggered directly – although it can occur concurrently with IgE mediated allergies and disorders.

In Mastocytosis, the problem can be making too many mast cells or having incorrectly shaped cells.  Very little is understood about Mast Cell Activation Disorder, which shares symptoms with Mastocytosis, but the usual clinical markers are not always present.  It’s theorized that in Mast Cell Activation Disorder, for unknown reasons, one’s mast cells become hypersensitive, ‘behave badly’, and thus are easily triggered to release their contents.

Mast Cell Disorders are not the same as Multiple Chemical Sensitivity.  But some people with MCS may be incorrectly diagnosed and actually have a mast cell disorder.  In his article called The Role of the Brain and Mast Cells in MCS, Dr. Gunnar Heuser, MD described how he tested a number of his MCS patients for markers that indicate mastocytosis or a mast cell activation disorder. A surprising number turned up positive.  Dr. Heuser postulates:

“…that chemical injury can trigger a mast cell disorder which in turn can cause MCS.”

The renown MCS expert William J. Rea, M.D., F.A.C.S., F.A.A.E.M., from the Environmental Health Center in Dallas says,

“…mast cell disorders play a large role in chemical injury and it would be worthwhile for most suffering from EI [environmental illness] to be tested for mast cell dissociation, as there MAY BE treatments available that might be helpful in managing symptoms or even resolving the condition completely.”

The long list of symptoms associated with mast cell disorders can be found at the The Mastocytosis Society.   Some people are called “shockers” because they go into anaphylactic shock when triggered, whereas others are called “leakers” because their mast cells slowly leak their contents causing chronic symptoms.  The symptoms can range from mild to severe.  There are specific medical treatments that help many people reduce the symptoms of mast cell disorders.

After limiting my exposures to my particular triggers and taking medications recommended for mast cell disorders for a year, my serum tryptase level decreased, but did not re-enter the normal range.  It remains chronically elevated, but the elevation is relatively small compared to people with full on mast cell disorders.  Although my health has generally improved by staying away from triggers, I remain sensitive when exposed.  My triggers include aromatic hydrocarbons (like diesel fumes, charcoal lighter fluid, moxa, etc.), perfumes and fragrance, medicines like morphine and procaine, and many foods.  I’m not a “shocker”, at least not to date, but have a chronic response like a “leaker”.

The challenge to getting a proper diagnosis for a mast cell disorder is that there are literally only a handful of mast cell disorder specialists in the United States.  Mastocytosis itself is considered rare and few doctors are familiar with the disorder. Mast cell activation disorder has yet to even be classified as an actual diagnosis although suggested diagnostic criteria have been published in the journal International Archives of Allergy and Immunology in May 2011.

Mast cell activation may also be associated with hypothyroidism, autoimmunity, neoplastic disease, parasitic infestation, infection, and other disorders.  Or, your symptoms may be in response to Histamine Intolerance, which may be associated with reduced activity of the DAO enzyme (one of the two enzymes that processes histamine in the body, and can be tested for at Dunnywoody Labs in the U. S. and many alternative labs in Europe.  Although this is not a definitive test, since DAO levels change throughout the day, if you already have symptoms it may give you a clue as to one possible causative factor.
Most recently, I’ve learned that I have genetic polymorphisms that can cause an upregulation of specific CBS genes, which are thought to impact mast cell degranulation.  You can read my article CBS Gene Mutations and Mast Cell Degranulation about this.  In my view, this explains everything and has solved the riddle of my symptoms and elevated serum tryptase.  It also provides ways to work around the mutation so there’s less impact.