Haven't been on PR in a long time, have been using my online time to research hyperadrenergic POTS and treatments. There's a new paper published by Mayo Clinic, and it has an interesting mention of MCA in a subtype of POTS, which is Hyperadrenergic POTS, and it also has a subtype. Those with a norepinephrine level over 600 are considered hyper-pots, and a very few people have a norepinephrine level between 1000 and 2000. It is that subset of hyper-POTS patients that Mayo believes have MCA. My norepinephrine level is over 1400. The paper is interesting for anyone with POTS. http://www.mayoclini...0896-8/fulltext Have seen Dr. K on a number of occasions and due to having CFS, POTS and another illness with a strong mast cell component, and significant symptoms including facial flushing, nausea, vomiting, osteoporosis, bone pain, etc...She suggested on two occasions that I be tested for mastocytosis. It's not as simple as having a tryptase and a plasma histimine test done. I've been doing a lot of research on the topic, and there are several excellent mast cell forums that have an enormous amount of good information and people who are very, very knowledgeable about both mastocytosis and MCA as well as several syndromes/diseases with mast cell components. I found the name of a mast cell researcher and doctor who is an oncologist and hematologist at M C Anderson Hospital. In order to get an appointment I had to send all my test results for him to review before he would agree to see me. I have an appointment with him next Thursday, and hope to get to the bottom of this issue and find a way the best way to treat it. Because this doctor is also a researcher, I hope to learn more than I would from the average M.D. and will share what he has to say about mast cell issues in CFS, POTS and other diseases. Glad to see Mast Cells being talked about with CFS. In a post long ago I said something to the effect that mast cells will prove to be a big part of the CFS picture.