Chronic urticaria phenotypes in childhood: Clinical and etiological features and prognosis

Bal, F. Chronic urticaria phenotypes in childhood: Clinical and etiological features and prognosis. Hacettepe University Faculty of Medicine, Thesis in Pediatrics. Ankara, 2019. Chronic urticaria is a rare skin disease in children. In the literature, there are few studies on the prevelance, etiology and prognosis of chronic urticaria in children. Data on the characteristics and natural course of chronic inducible urticaria in children are almost non-existent. In this study, it was aimed to determine the distribution frequency of different urticaria subtypes of patients admitted to Hacettepe University Pediatric Allergy Clinic, to determine the laboratory and demographic characteristics of each urticaria subtype, the natural history of different types of urticaria and to determine the factors that will affect this course. The study included 427 patients who were evaluated as chronic urticaria between March 1, 2011 and March 1, 2019. The demographic characteristics of the patients and the results of the laboratory tests were evaluated retrospectively. Prognosis of chronic urticaria patients were evaluated when they came for control visits. Of the patients diagnosed with chronic urticaria, 72.6% were diagnosed with chronic spontaneous urticaria (CSU) and 27.4% of them were evaluated as chronic inducible urticaria (CIU). Chronic inducible urticaria was determined as symptomatic dermographism in 65%, cold urticaria in 17%, cholinergic urticaria in 15.4%, aquagenic urticaria in 1.7% and late pressure urticaria in 0.9%. Serum basal tryptase levels in patients with cholinergic urticaria and cold urticaria were higher than patients with dermographism (p = 0.02). In chronic spontaneous urticaria patients, autoimmunity and infections were the most frequently detected factors. In children with chronic spontaneous urticaria; If urticaria started before the age of 2, the prognosis was worse than those starting after 2 years of age. When the prognosis of CIU pediatric patients is considered, the rates of remission at the end of the first year, third year and fifth year were 9.6%; 25.3% and 34.7% respectively. In this study, data have been obtained to contribute to the literature about the clinical course of CIU pediatric patients. Additionally, detection of higher basal tryptase levels in cold urticaria and cholinergic urticaria patients will help to clarify the etiopathogenesis of CIU and the treatment approaches. Key Words: Chronic urticaria, inducible urticaria, child, prognosis, tryptase