Mast Cell Disorders Forum

Mast Cell Disorders Forum
http://mastcelldisorders.wallack.us/yabb/YaBB.pl General Mast Cell Disorders Discussion >> General Mast Cell Disorder Discussion >> How many of us are out there? http://mastcelldisorders.wallack.us/yabb/YaBB.pl?num=1411864134 Message started by CrystalG on 09/27/14 at 13:28:54

Title: How many of us are out there?
Post by CrystalG on 09/27/14 at 13:28:54

I am wondering how many of us with Mast Cell Activation Syndrome there are in the United States and in the World? I know it is a rare disease, but wondering if anyone knows a rough estimate of how many people in the US and around the world have this?

Title: Re: How many of us are out there?
Post by Bruce Hart on 09/27/14 at 17:12:31

Mastocytosis is rare, but the recently recognized MCAS is believed common by some top MCAD researchers with "recent preliminary prevalence estimates of 14-17%".[1]

1. www.allergysa.org/journals/August2014/ThePresentation.pdf

Title: Re: How many of us are out there?
Post by Spartako on 09/28/14 at 02:11:53

I know some people who seem to have mast cell issues and I think that the numbers of up to 17% are way to high. If some people with fibromyalgia and irritable bowel syndrome have underlying mast cell activation syndrome maybe the count will go up to 3-5%.
But people who know they got mast cell activation syndrome are very few. Also the symptoms can vary from very mild to severe.

http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3787002/

Quote:

Thus, the prevalence of MCAD determined in this study fits well to these previous indirect estimations, suggesting that it is likely to reflect the true prevalence of the disease in the German population. A limitation of our study with regard to this conclusion may be that, in first-degree relatives and healthy control subjects, the diagnosis was made according to self-declared information. The sensitivity of the questionnaire to detect MCAD is high (reflected in the significantly increased prevalence of reported symptoms in MCAD compared with the control group) but it could not be reassessed whether the information about the absence or presence of relevant further diseases (differential diagnoses) were valid. Hence, the prevalence could be overestimated. In addition it cannot be excluded that recall bias in our controls has resulted in an overestimation of the prevalence of MCAD in the general population. Only 27% of the people whom we originally contacted completed the questionnaire and, since the purpose of the study and the disease were described in the addressing letter, affected people may have preferentially responded to our request. Therefore our estimation of the prevalence must be viewed with caution and should be taken as a stimulus to pursue more epidemiological studies in the future.

Title: Re: How many of us are out there?
Post by CrystalG on 09/28/14 at 04:23:18

Thank you Bruce and Spartako. It seems it is hard to get an accurate estimate as most people go undiagnosed or are mild cases. I have been asked this question so many times and never know how to answer.

Title: Re: How many of us are out there?
Post by Bruce Hart on 09/29/14 at 02:26:26

Yeah I think it will be a while before we have any good accurate estimates. I think Dr. Afrin believes MCAS is common for other reasons, as do I.

If you add in the possibility many with asthma, migraines and especially multiple chemical sensitivity (MCS) have MCAS then it may meet or exceed that 14-17% people with MCAS in the general population. The biggest reason I think MCAS is likely common is because MCS is reported as very common, statistics vary but I think always above 12%. And MCS fits with MCAS extremely well. When we get better diagnostics I'm eager to see what percentage of those with MCS can be confirmed to have MCAS.