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Mast Cell Activation


I am continually learning about new things...and it certainly is an important time for discoveries in auto-immune disorders, the immune system, the nervous system and how they interact. Researchers continue to learn more about these types of conditions while also realizing they have a lot yet to understand. The internet and the ability to find scores of information on so many topics will either drive a person insane or give them hope of what new understandings are taking place. The ability to become connected to so many others with similar experiences can also be encouraging - which leads me to my next area of interest - mast cell activation.

Mast cells originate in bone marrow and move through our blood to various tissues throughout most of the body including connective tissue, skin, stomach, intestines, lining of the lungs, lymph nodes and other areas. They are now thought to play a big part in regulating our immune system, taking part in wound healing (think of the itchiness you sometimes feel as a wound heals) as well as the growth of blood vessels. Mast cells are needed for survival and researchers say no one has too few - you wouldn't survive otherwise. But they are finding that some people have too many (mastocytosis) or some might have a normal number of mast cells that are too easily triggered into an allergic response (mast cell activation syndrome or MCAS). An allergic response occurs when the mast cells are triggered into releasing histamine which can cause any or more of the following: hives, gastrointestinal issues, wheezing, watering eyes, flushing, low blood pressure, anaphylaxsis, anxiety, dizziness, etc. Taking an antihistamine blocks the response the released histamine creates in the body by not letting them bind to certain receptors. While corticosteroids (very different from anabolic steroids) taken ahead of allergic reactions, can actually help stop the histamines from being released into the body.

There are lots and lots of sites that talk about mast cells and their responses. I found this blog written by someone who has celiac but also mast cell activation syndrome - Mast Cell Activation Syndrome Madness - easy to read and understand. I just sent a copy of the link to a relative struggling with similar symptoms as Meghan but with severe stomach pains. So many of the symptoms between auto-immune illnesses overlap making a diagnosis difficult - and why so many turn to the internet to self-diagnose. (Read my blog post Is POTS Really Auto-Immune for research that points to POTS and auto-immunity). It is interesting that females make up the majority of the patients with MCAS - similar to POTS and several other auto-immune disorders.

A few weeks ago Meghan started to become itchy during swim practice. Everywhere she scratched, even lightly, huge hive-like welts or the more technical term urticaria (who knew?) appeared. She said she was scaring her teammates who thought she must have been in a terrible fight to be covered in so many welts. But by the time we got home, they were completely gone. Not a trace. This happened for 3 days with Claritin helping slightly to reduce the itchiness. That week we also had one of her antibody transfusions, called IVIG, scheduled which includes a recovery day from the effects of the transfusion itself. When she returned to swimming, no hives. We are now wondering if the IVIG played a role in suppressing her mast cell activity. Here is an article about a girl with severe mast cell activation, POTS and EDS that also receives IVIG treatments. "Bubble Girl is Allergic to Life." It has a link to a site that talks about IVIG and how it works - it talks about IVIG slowing down the inflammatory process or helping to regulate an over active immune system. These are all interesting things to read and make note of. I am not a doctor or a researcher but like to read about how things work. Meghan receives IVIG for her POTS - with the thought that the good antibodies overwhelm the bad antibodies that cause her illness. But it may also help with MCAS.

Some interesting triggers of hives or mast cell activity that don't include food are: extreme temperatures of either hot or cold, exercise, emotional or physcial stress, strong scents, or sometimes chemicals. Some things to note for Meghan during that time - it was her first finals week for high school. She was extremely stressed about doing well and since her body already tricks her into feeling anxious from the POTS, her anxiety was through the roof. Practice is also very physically demanding. The IVIG allows her to do what most POTS patients are not able to do - heavy, physical exercise. The pool is also cold. The pool is full of chlorine. And she was nearing the end of her IVIG treatment period. Lots of potential triggers and hard to determine if it was one thing or a combination or something totally unrelated!

There are also triggers that include food, outdoor allergies, insect bites and other environmental allergens. I have noticed that she has certain foods that cause a tingling sensation when she eats. These could be mast cell reactions. Another interesting article a friend sent me is on montelukast (Singulair) asthma medication. Meghan takes this to help control her asthma when we determined that advair was possibly irritating her lungs as she inhaled it. Singulair is in tablet form but also has some interesting anti-inflammatory effects. The article is ridiculously long and slightly hard to read (I took multiple breaks while reading it) but highly informative.

Dysautonomia International also has a great article called: A Tale of Two Syndromes - POTS and MCAS that has great information on how the two overlap and some cautions on testing for MCAS. Having occasional hives that are easily treated with a low dose antihistamine does not mean you have mast cell activation syndrome by any means. But if you have POTS, another auto-immune disorder or other autonomic issue, it could be something to explore or ask your doctor about. Or if you have repeated, allergic reactions that interfere with your life. When I asked a nurse about mast cells a month or two after Meghan was diagnosed with POTS, she dismissed me and said it was very rare. And to the average, healthy person it may be. I don't have stats on it. But if you have POTS, there seems to be a connection.

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