Association of postural orthostatic tachycardia syndrome, hypermobility spectrum disorders, and mast cell activation syndrome in young patients; prevalence, overlap and response to therapy depends on the definition.

This study explores the prevalence and overlap of postural orthostatic tachycardia syndrome (POTS), hypermobility spectrum disorders (including hypermobile Ehlers-Danlos Syndrome), and mast cell activation syndrome (MCAS) in young patients. It highlights the issue of varying prevalence rates depending on the diagnostic criteria used for each condition. Retrospective analysis of 100 POTS patients shows JHD prevalence ranging from 13% to 34%, and MCAS prevalence ranging from 2% to 87%, depending on definitions applied. Findings indicate that overly strict diagnostic criteria can lead to underdiagnosis and missed therapeutic opportunities, as patients adhered to broader clinical criteria rather than stringent lab-based ones, showed similar responses to MCAS therapies.