Chronic urticaria: etiology and natural course in children.

BACKGROUND Chronic spontaneous urticaria (CSU) in childhood is infrequent, and information about the disease in children is limited. We attempted to investigate its etiologic factors, natural course, and predictors of prognosis. METHODS All children aged ≤ 18 years followed for CSU during an 8-year period were analyzed retrospectively, and the final outcomes were queried via a telephone interview. RESULTS One hundred patients (male/female ratio 1.27) with a median age of 9.2 years (range 0.7-17.2) at symptoms onset were evaluated. The median follow-up was 2.5 years (range 0.2-18.1). An autologous serum skin test was positive in 46.7% of the subjects (n = 45), with a female predominance (71.4%) (p = 0.023). In 13.8% of the children, ANA titers were over 1/100. Food allergy (n = 1), thyroid autoantibodies (n = 3), possible collagen disease (n = 1), and drug usage (deferoxamine) (n = 1) were found to be associated factors. Infections could not be confirmed as the cause of CSU. Recovery was seen in 16.5, 38.8, and 50.0% of the children after 12, 36, and 60 months, respectively. Though in multivariate analysis none of the factors, including age, gender, autologous serum skin test positivity, the presence of angioedema, or other allergic diseases, appeared to predict the prognosis, in univariate analysis being female and being older than 10 years of age predicted an unfavorable prognosis. CONCLUSION The etiology of CSU in children is mainly related to an autoreactive background, as in adults. CSU has a favorable prognosis, and resolution is seen in half of the children within 5 years. Girls older than 10 years may have an unfavorable prognosis.