Diagnosis of mast cell activation syndrome: a global "consensus-2".

The document discusses the growing recognition of mast cell activation syndrome (MCAS) and the two main diagnostic criteria proposed for its diagnosis, termed "consensus-1" and "consensus-2." It highlights the differences in these proposals and addresses the potential for overdiagnosis with "consensus-2" and underdiagnosis with "consensus-1." Given the increasing recognition that MCAS may affect up to 17% of the general population and the potential benefits of treatment, the authors suggest that diagnosing MCAS using either set of criteria is currently valid and beneficial until more definitive research is conducted.