“…Individuals with rare diseases experience lengthy diagnostic odysseys, increased morbidity, and adverse health outcomes at disproportionate rates. 1 , 2 , 3 Similarly, persons living with undiagnosed primary immune disorders/inborn errors of immunity (IEI) often come to diagnosis late with resultant suboptimal health status. 4 , 5 Reasons for delayed diagnosis among individuals with IEI include lack of IEI sign and symptom recognition by health care providers, clinical heterogeneity masking the primary disorder, and suboptimal use of health system science to detect patients within populations.…”