Clinical Follow-Up, Etiology, and Predictors of Progression to Chronic Urticaria in Children with Acute Urticaria: A Guideline-Based Study

Background: Acute urticaria (AU) is a common dermatologic emergency in children, frequently leading to unnecessary diagnostic work-up and treatment. Although usually self-limited, approximately 5%–10% of pediatric AU cases are reported to progress to chronic urticaria (CU). Evidence-based data on etiologic causes, real-world adherence to current guidelines, and predictors of chronicity in pediatric AU remain limited. We aimed to evaluate the diagnostic approaches, etiological factors, and treatment outcomes at initial presentation of pediatric AU, and to identify predictors of progression to CU during follow-up. Methods: This single-center prospective cohort study included 210 pediatric patients diagnosed with first-episode AU (median age: 5.4 years [interquartile range (IQR): 2.6–8.0], 54.8% male). Etiologic assessment, diagnostic testing, and treatment were performed according to the European Academy of Allergy and Clinical Immunology, Global Allergy and Asthma European Network, and Asia Pacific Association of Allergy, Asthma and Clinical Immunology guidelines. Suspected and confirmed triggers were recorded. Patients were followed for a median duration of 5 months (IQR: 1.5–8), with a range of 1.5–14 months. Logistic regression was used to identify predictors of CU. Results: A suspected trigger was identified in 63.3% of cases, and a confirmed etiology was established in 61% after diagnostic evaluation. Infections were the leading cause (55.2%), followed by physical stimuli (5.2%) and food (0.5%). No drug-induced urticaria was confirmed. Sixty-five and seventh tenths percent of patients required no diagnostic testing, and 95.2% achieved complete remission with standard antihistamine treatment. Only 4.8% progressed to CU during follow-up. Urticaria lasting more than 7 days (odds ratio [OR]: 14.1, 95% confidence interval [CI]: 2.62–75.73, P = 0.002) and physical stimuli (OR: 22.8, 95% CI: 2.95–177.19, P = 0.003) independently predicted CU, while age, atopy, and baseline severity were not associated. Conclusion: Guideline-based conservative management provides excellent outcomes with minimal testing. Prolonged duration and physical stimuli are key predictors for chronic progression, underscoring the importance of close follow-up in these patients.