I see a nurse too as my primary care person. I think yours sounds pretty darn good--she has experience with it and is giving you the exact right meds for it. I think I would stick with her for primary care. Your GP would be the DR that the nurse works under.
Now for the expert--there is a Dr Butterfield at Mayo in MN, who is a masto expert. We've had some mixed reviews about him--not the best of bedside manner...but he is very active with research and just published more findings about masto recently, so he is better than just picking a DR out of a hat. Im sure other people will post to you here with some other suggestions.
Youre on a lot of the right meds--but you didnt say how much you are taking. Most of us need much higher doses than the average person who does not have masto. You still sound under-medicated to me or your reactions would be less and possibly stop. Tell us what doses of which med you take and how often.
Make SURE you keep copies of all your lab tests--like that high mast cell count in your colon. I would bet youre having trouble with your bladder too--mast cells migrate from the colon to the bladder in some people and with a high count I would bet you are having problems with bladder spasms and getting to the bathroom in time. We can suggest some meds for that if you do have that problem.
Now about Bone Marrow Biopsy. It is important , it tells you often which type of mast cell disorder you have by what they find, it gives you an idea of the progression of your disease and it gives you a baseline for watching your progress in , say in another 5 years. I would wait for this until you see an expert. It has to be done in a very specific way and the expert should do it.
As far as your GI doc, he is no helps to you, I see. That bloody diarrhea is a concern and your expert will handle that--it again means you are under medicated and we need to stop that type of reaction quickly.
I would guess (only) that you have a type of SM with bleeding disorder involved. A lot of us have that type, all treated the same way, same meds.
For now you need to READ a lot of info on this board--low histamine diet, emergency protocals... and start an ER notebook for yourself. Also time for you to start a daily diary of what you ate/how you feel/level of activity... this will help you track down your triggers. You have to be proactive and dont ever feel bad standing up for yourself.
We have your back and you can ask us anything
Hugs
Ramona