If people were trees, I’d guess that one sapling in every forest has heard of mast cell activation syndrome. That’s most likely because fewer than one sapling in every forest has been diagnosed with the illness. But, according to the handful of medical researchers working on understanding the condition, there might be a pretty hefty stand of trees surrounding that one sapling that all have a mast cell disorder; they just don’t know it. MCAS manifests as such a strange variety of symptoms that it is usually misdiagnosed as two or three or even ten other concurrent illnesses. The limited number of patients who have been diagnosed might be the tip of a very unpleasant iceberg.
I was diagnosed first with chronic fatigue syndrome and then with MCAS. That makes sense, because it now appears that MCAS may be chronic fatigue’s daddy.* In fact, MCAS may have an entire brood of distressing progeny: fibromyalgia, multiple chemical sensitivities, POTS, irritable bowel syndrome, and much more. The common thread here is that all these conditions are of unknown origin and were first dismissed by medical science as hooey. It’s possible—and I stress possible, because a LOT more research is needed—that MCAS is the root (or a root) of all these branches. If science can figure out what causes MCAS and how to cure it, we may be on our way to curing a whole tree of suffering.
So, what is mast cell activation syndrome? Here’s the Sesame Street explanation (keeping in mind that I am myself a student of MCAS, not an expert):
Mast cells were our bodies’ first defense against cellular invaders. Apparently, for a time, they were our only defense. They were the army before we had the air force, navy, and marines. As such, they had to do all the work of defending our bodies. Eventually, our bodies developed a more sophisticated defense, or immune, system, with lots of players doing the work the mast cells had once done on their own. But the mast cells haven’t been put out to pasture—oh no. They’re still around and playing an important part in our bodies’ defense system. Unfortunately, in some people, the mast cells are working way too hard. Maybe they didn’t get the message that they’ve got plenty of help now? They are not standing down at all, ever, and are firing on the very things they are meant to protect. They are overly activated, hence the name mast cell activation syndrome.
Mast cells originate in the bone marrow and then spread throughout every type of tissue in the body. They’re not numerous, but they do tend to concentrate where the body interacts with its environment—the skin, the digestive system, and the respiratory system. So symptoms of mast cell activation can include itching, flushing, rashes, hives, wheezing, sneezing, difficulty breathing, anxiety, panic attacks, low blood pressure, rapid or racing heart rate, gastrointestinal distresses of all types, sleep disturbances, and . . . yep . . . debilitating fatigue.
There’s so much to explain about MCAS. As I learn more, I’ll try to pass it along.
Julie
My primary sources for this post are both from Lawrence B. Afrin, M.D. One of his presentations is available on YouTube as Mast Cell 101, and his book, Never Bet Against Occam: Mast Cell Disease and the Modern Epidemics of Chronic Illness and Medical Complexity (Sisters Media, 2016) is widely available.
*When I originally wrote this post, I was under the impression that ME/CFS is caused by Mast Cell Activation Syndrome (MCAS). I have since learned that MCAS may more likely be a comorbid condition with ME/CFS. Or not. At this point, nobody really knows.