It is a positive. Did you have any other positive labs?
No not yet
If that is saying your value is 232, and the reference range is 30-200, then your lab shows a slight elevation. You need one more positive lab to meet an MCAS mediator criteria. It can be a second test of N-Methylhistamine on another date, or if the Prostaglandins were also ran in that sample and come back elevated, then that criteria is met. You then also need to meet the other two - symptoms of mast cell activation and a positive response to treatment.
If you can’t capture anything else on urine, you can try for blood tryptase. A baseline test that rises by 20% plus two during a reactive draw shows a “meaningful increase” in tryptase. So, if your baseline tryptase is 5, your second reactive draw would need to be an 8 or higher. If you can meet that formula with tryptase, urine results aren’t needed.
The lab messed up the prostoglandin sample
Sheryll tryptase was normal in blood work. Do I have to retest?
Kristel normal doesn’t matter with MCAS for tryptase. Everyone (or almost everyone) with MCAS has a normal tryptase. Can you capture the rise of 20% plus 2 from the baseline? If so, it counts as a “meaningful increase”. What was your baseline tryptase?
Sheryll I'll check when I get home. Also, does it matter if all of his was tested when not in flare?
When not in a flare = baseline. Initial testing should be done at baseline.
Sheryll got it. Thanks so much!