Laboratory Tests
Consenting patients underwent additional blood tests for baseline IgE, tryptase, c-reactive protein (CRP), and a complete blood count (CBC). Absolute blood eosinophils, total IgE, tryptase, and CRP were considered as dichotomous variables. An absolute blood eosinophil value >0.60x109 cells/L, total IgE level >240IU/mL, tryptase >13.5ug/mL, and CRP >5mg/mL were categorized as elevated based on the upper limit reference level for these biomarkers at the Montreal Children’s Hospital.