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.