Chronic Urticaria in Children – Demographics, Clinical and Laboratory Characteristics and Long Term Follow-up

Background: Chronic urticaria (CU) is defined as the presence of hives most of the days for at least 6 weeks. The incidence of CU is 1.8% in adults, and 0.1%-0.3% among children. Data regarding CU in children is limited and based on small series.

Objectives: To investigate the demographic, clinical and laboratory characteristics of children with CU. In addition, to examine the association between CU and other co-morbidities.

Methods: Medical records of children (<18y.o) treated at the Allergy and Clinical Immunology clinic at Meir Medical Center between 2002 and 2018, and diagnosed with CU, were retrospectively reviewed. Collected data included demographics, and clinical and laboratory findings were extracted and analyzed.

Results: 250 patients were included in the study (54.4% were females). The mean duration of the urticaria was 12.25±15.2 months. CU was more prevalent in adolescents (>13y.o) compared to younger age groups. Girls predominated during adolescence (59.8%), and in the younger age groups there is no difference between sex (49.2% girls, p=0.92). The prevalence of atopic dermatitis(17.2%), allergic rhinitis(16%), asthma(13.2%) and food allergy(3.2%) was found to be higher than in the general pediatric population. The prevalence of thyroid diseases was increased as well(3.6%). 153 of the children (61.2%) were treated sufficiently with low-dose anti-histamine drugs.

Conclusion: CU in children is more common in adolescents and responds well to low-dose anti-histamines in the majority of cases. The prevalence of atopic diseases was higher than expected in the general population, suggesting CU in children to be a more Th2 type of disease.