Nationwide epidemiology and healthcare burden of pediatric anaphylaxis in Thailand: A population-based study, 2019-2023.

BACKGROUND: Anaphylaxis is a potentially life-threatening allergic reaction requiring prompt recognition and treatment. Although increasing trends in pediatric anaphylaxis have been reported worldwide, nationwide epidemiological data from Southeast Asia remain limited. This study aimed to investigate the epidemiology, clinical characteristics, and healthcare burden of pediatric anaphylaxis in Thailand using a national administrative database. METHODS: We conducted a nationwide retrospective study using the Thai National Health Security Office database from 2019 to 2023. Children aged 1 month to <18 years hospitalized with anaphylaxis were identified using ICD-10-TM codes. Demographic characteristics, triggers, comorbidities, complications, and outcomes were analyzed. Temporal trends, regional variation, and factors associated with in-hospital mortality were evaluated. RESULTS: A total of 42,290 pediatric anaphylaxis hospitalizations were identified, increasing from 7877 cases in 2019 to 10,519 in 2023. School-aged children and adolescents accounted for the largest proportion, with male predominance (59.4%). Food-related reactions were more common in younger children, whereas insect-related reactions were more frequent in older age groups. Most patients had favorable outcomes, with a median hospital stay of 1 day and in-hospital mortality of 0.04%. Severe complications and certain comorbidities were associated with increased risk of adverse outcomes. Geographic variation was observed across regions. CONCLUSIONS: Pediatric anaphylaxis hospitalizations in Thailand increased during the study period, while mortality remained low. Age-related trigger patterns and regional differences highlight the need for improved surveillance, documentation, and targeted prevention strategies.