Clinical and etiologic evaluation of the children with chronic urticaria.

BACKGROUND: Chronic urticaria (CU) is a skin disorder defined as daily or almost daily exhibition of pruritic and transient wheals that last for >6 weeks. CU is divided into two subtypes: chronic spontaneous urticaria (CSU) and chronic inducible urticaria (CIndU).

OBJECTIVES: To evaluate the clinical features, possible causes, associated findings, and laboratory results of different subtypes of CU in children according to a new classification.

METHODS: In this study, we evaluated the clinical features, laboratory investigations, and provocation tests of children with different subtypes of CU according to a new classification.

RESULTS: Two hundred and twenty-two children (59.9% girls) were enrolled in the study. Of the study patients, 59.9% and 40.1% were diagnosed as having CSU and CIndU, respectively. Antithyroid antibody levels were positive in 7.1% of the patients with CSU, 32.8% of the children had positive 14C-urea breath test results, and 6.5% of the patients had positive stool examination results for parasites. Autologous serum skin test results were positive in 53.5% of the patients with CSU. Of the patients with CIndU, 77.5% had symptomatic dermographism, 16.8% had cold urticaria, 2.2% had cholinergic urticaria, 2.2% had solar urticaria, and 1.1% had aquagenic urticaria.

CONCLUSION: Children with CSU represent the majority of patients with CU, and more than a half of these patients might have autoimmune urticaria. Symptomatic dermographism was the most common type of CIndU.