Systematic evaluation of allergic phenotypes of rhinitis in children and adolescents

Background Three allergic phenotypes of rhinitis have been described in adults: allergic rhinitis (AR), local allergic rhinitis (LAR), and dual allergic rhinitis (DAR, coexistence of AR and LAR). Nevertheless, most centers follow a diagnostic approach only based on skin prick test and serum allergen–specific IgE (collectively called atopy tests, AT). This approach prevents the recognition of LAR and DAR, the diagnosis of which requires a nasal allergen challenge (NAC). Here, we investigate the existence of LAR and DAR phenotypes in children and adolescents, and the misdiagnosis rate associated with a work‐up exclusively based on AT. Methods Clinical data were obtained during physician‐conducted interviews, and AT and NAC were systematically performed in 5‐ to 18‐year‐old patients with chronic rhinitis. The misdiagnosis rate was defined as the proportion of cases where AT and NAC results were discordant. Results A total of 173 patients (mean age 15.1 years, 39.9% male) completed the study. AR (positive AT and NAC), LAR (negative AT and positive NAC), DAR (positive AT and NAC for some allergens and negative AT and positive NAC for other allergens), and non‐allergic rhinitis (negative NAC) were diagnosed in 45.7%, 24.9%, 11.6%, and 17.9% of individuals, respectively. The clinical profile was comparable among allergic phenotypes, but allergic patients had a significantly earlier rhinitis onset, higher conjunctivitis prevalence, and more severe disease than NAR individuals. A diagnostic work‐up exclusively based on AT misclassified 37.6% of patients. Conclusions LAR and DAR represent relevant differential diagnosis in pediatric rhinitis. NAC increases the diagnostic accuracy of clinical algorithms for rhinitis in children and adolescents.