• Welcome to Crohn's Forum, a support group for people with all forms of IBD. While this community is not a substitute for doctor's advice and we cannot treat or diagnose, we find being able to communicate with others who have IBD is invaluable as we navigate our struggles and celebrate our successes. We invite you to join us.

Why don't GI docs seem to think of mast cells in DDX of tough cases?

I'm just wondering. After loads and loads of tests and no real answers to why I bleed more often than not with BMs, a few months ago, it occurred to me to ask my GI doctor if the fact that I sometimes broke out in inexplicable hives before diarrhea attacks and had episodes of flushing was significant.

Turns out, it *is* significant -- enough to run tests to rule out carcinoid syndrome, pheochromocytoma, and a handful of others. Fortunately, I don't have any of these things going on.

But I saw a specialist last week for some other issues I've been dealing with, and he determined pretty fast that I probably have a problem with mast cells -- either too many of them or erratic and excessive activations of the the ones I have.

He put me on a combo of Zantac and Claritin, two histimine antagonists that work with different mechanisms, to help with my skin problems. He said there'd be a strong chance some of my GI issues would clear up too. Sure enough, while my gut is still kind of a mess, it's better than it's been in a while. The reddish-purple welts I had all over my legs have completely vanished in under a week, and I don't get nearly as itchy at random anymore.

Anyway, I've got some GI follow-up for a bunch of venous malformations in my small intestine, and this new doc said that since they'll have to do an upper and lower scope to cauterize the veins anyway, I should ask for a biopsy and stain for mastocytic enterocolitis.

It's all got me wondering ... it seems mast cell issues are fairly common. Given the fact that they're common, why hasn't a single one of the four GI docs I've seen even mentioned them? I mean, I've even had scopes with obvious inflammation that biopsied normal -- but no one stained for mast cells at the time.

Ok. This was partly just a vent, but I'm genuinely curious -- anyone know why mast cell problems so rarely enter the gastroenterology differential diagnosis for people with intestinal inflammation without an obvious cause?


Super Moderator
I don't know the answer but I've been in a similar boat. I haven't had itchy welts or anything like that, but I wanted my GI to stain my biopsies for mast cells to at least rule out mastocytic enterocolitis. He told me that ME is so rare that doctors hardly ever stain for mast cells. I was like, well, wouldn't it probably be less rare if you guys actually looked for it more?? I mean, if they actually looked for it, they might find some more cases of it, right? It seemed like really incorrect circular logic. They don't look for it so they don't find it, and since they don't find it, they don't look for it. Seems very odd to me! I likely don't have ME so I wasn't too bothered, but that line of thinking by my doctor is troubling to me.