Autonomic function testing and symptom severity in patients with suspected mast cell activation disorders.

We assessed both objective and subjective measures of autonomic severity in patients with formally classified mast cell activation disorder (MCAD), hereditary alpha tryptasemia (HaT), and systemic mastocytosis. In all subjects, autonomic disease severity was objectively mild but subjectively moderate to severe. The presence of MCAD did not yield consistent differences on subjective or objective severity measures, although HaT did associate with lower objective (but not subjective) severity measures. In conclusion, assessment of MCAD and related disorders can be conducted using formal classification criteria, and in those with suspected dysautonomia, the workup should incorporate objective and subjective measures of dysautonomia.