Mast Cell Activation Syndrome: MCAS


Mast Cell Activation Syndrome (MCAS) may be at the root of widespread chronic, debilitating illness. It is an ‘emerging’ illness – not that it is new, but rather in that it has only recently been named and become the subject of attempts to define diagnostic criteria, and the medical community is only just beginning to be aware of its existence.

Mast cells are specialized white blood cell that play a critical role in the innate immune system and its response to threat. When stimulated, these cells release a host of powerful mediator substances such as histamines that result in inflammatory responses in multiple systems. Inappropriate and excessive release of these chemical mediators lead to myriad symptoms in multiple systems that change in severity and clinical presentation over time, often becoming chronic and debilitating.  

The common symptoms of MCAS can involve the cardiovascular, gastrointestinal, respiratory, neurological, and musculoskeletal systems. Inflammatory processes in the brain can add cognitive and memory dysfunction to this mix.  Chronic infections that lead to vascular inflammatory diseases and autoimmune diseases play a leading role in triggering and activation of mast cells. Because so many systems can be involved in varying ways that confound diagnosis and effective treatment, MCAS patients often struggle to understand their own conditions and to find experienced physicians with enough suspicion and experience to identify the underlying causes of illness. 

MCAS Registry

FSID also is launching a registry where MCAS patients will be able to securely enter their own key clinical details and receive information on how they compare with other patients in terms of likely causes and treatment possibilities.

For more information about this registry or to contact our patient research center, please contact us.