Hi, Raph.
I was not able to find out anything useful about the relationship of mast cell issues and ITP. However, I seem to have stumbled into a treatment for them as part of a clinical trial I have been enrolled in since February 2023. And that is to take a low dose of dexamethasone over a long period of time.
The drug trial is for a new BTK inhibitor called Rizilbrutinib. I go to the University of Southern California once a month to check on my progress. Because my platelet count had been below 5 for most of the previous 6 years, the doctor running the drug trial wanted to raise my platelets before starting the trial and make sure they were around 30 even if I was not receiving the trial drug during the first 6 months (this was a double-blinded study and so the doctor and his staff didn't know if I would be receiving the drug or a placebo at first.) So he put me on Doptelet. It didn't work by itself at first, so we added 1 mg of Dexamethasone to the protocol, and that succeeded in raising my platelets to safe levels over 30. Over time, I have taken 40 mg of Doptelet and .5 mg of Dex daily in addition to the trial drug. Since then, my platelets have reached a high of 328 and have stayed in the safe zone above 30 for all but 2 weeks since starting the trial.
I had developed an allergic reaction to NPlate about 10 years ago, which stopped working after 14 months and led to my developing salicylate sensitivity. As I result, I broke out in itchy rashes whenever I tried to eat most fruits and vegetables. About six months after starting the clinical trial, I realized I could eat these foods and no longer broke out in rashes. I credit the small doses of dex I have been taking during this time for my success in getting over my food sensitivities.
My platelets have been stable and over 100 (around 180) for the past two months. So I am starting to wean off the dex, and after that, will start reducing the Doptelet and see if I can get off of that, too. I don't know yet if the study drug will work on its own. But I am very happy to be free of the salicylate sensitivity and be able to eat most foods again.
So if you are experiencing allergic symptoms and dex seems to work for you, you can ask your doctor to prescribe 1 mg of dex and see if that helps raise your platelets. My platelets went up to 30 within 1 week of starting the Dex and Doptelet combo, even before I started the clinical trial. So that may be an option for you to try. Low dose dex might even help you to get better results with Eltrombopag. (Note that prednisone doesn't work for me even though dex does.)
Also, I had previously tried the short-term dex protocol (4 days at 40 mg/day), and while that temporarily raised my platelets, they fell back to less than 5 a few days after getting off it.
Good luck with this. Let me know what happens.
Best regards, Cathy
Best regards, Cathy