The diagnosis of Mast Cell Activation Syndrome (MCAS) can be challenging because the symptoms can overlap with many other medical conditions, and there is no single definitive test to diagnose it.
MCAS is typically diagnosed through a combination of clinical evaluation, laboratory tests, and sometimes specialized assessments.
Clinical evaluation: can include medical history, symptoms review, triggers identification, physical examination, and response to treatment.
Laboratory tests: can include tests for tryptase, histamine metabolites, cytokines, as well as for allergies and trigger sensitivities; more advanced cases may also do genetic testing.