Chronic Urticaria in Children -- New Insights from a Large Cohort

Background: Chronic spontaneous urticaria is well-described in adults, but less so in children. The aim of this study is to describe the demographics, clinical characteristics, comorbidities, and outcomes of children with chronic, spontaneous urticaria. Methods: This retrospective study followed children up to 18 years-old, diagnosed with chronic spontaneous urticaria, between the years 2002-2018 and treated in a tertiary referral allergy and clinical immunology center. Data including demographics, clinical characteristics, comorbidities, treatments and outcomes was extracted from electronic medical records. Results: Records of 380 children coded to have chronic urticaria were reviewed, of which 250 (65.8%) fulfilled the diagnostic criteria for chronic spontaneous urticaria. There were 136 females (54.4%). Mean age at diagnosis was 11.4 years, 122 (48%) were adolescents. The average duration of chronic spontaneous urticaria was 12.25±15.2 months. The urticaria in 208 children )83.2%) resolved within 24 months. Eighty-seven patients (34.8%) had at least one atopic disease. Atopic comorbidities included atopic dermatitis in 17.2%, allergic rhinitis in 16%, asthma in 13.2% and food allergy in 3.2%. Eighteen patients (7.2%) had a concomitant autoimmune disease. Nine (3.6%) had thyroid disease. Conclusions and clinical relevance: Chronic spontaneous urticaria in children is a self-limited disease with favorable prognosis. Atopic diseases are more prevalent in children with chronic spontaneous urticaria than in the general pediatric population; increasing the possibility of a special subgroup of TH2-related chronic urticaria in children.