Characteristics of anaphylaxis from tertiary-care hospital in lower northern Thailand: A ten-year retrospective cross-sectional study.

Background: The prevalence and etiology of anaphylaxis vary based on geographic regions, study design, and definition used. Anaphylaxis leading to emergency department visits and hospitalizations has increased worldwide.

Objective: The prevalence and etiology of anaphylaxis vary based on geographic regions, study design, and definition used. Anaphylaxis leading to emergency department visits and hospitalizations has increased worldwide.

Methods: A cross-sectional retrospective analysis of medical records from patients with ICD-10 confirmed anaphylaxis was performed at Naresuan University Hospital between March 2011 and February 2021.

Results: We identified 439 anaphylaxis episodes in 381 patients within 10 years. The average annual occurrence rates of anaphylactic episodes were 25.0 per 100,000 outpatient and emergency department visits and 11.2 per 100,000 inpatient visits. Both pediatric and adult anaphylaxis events increased annually, from 13.3 (children: 20.5, adults: 12.4) in 2012 to 46.6 (children: 52.6, adults: 46.1) episodes per 100,000 visits in 2021. Peak incidence was observed in adolescents and young adults. Food was the most common trigger, with shrimp and fried insects being predominant. Risk factors for severe anaphylaxis were underlying cardiovascular diseases, drug triggers, and wheezing. Epinephrine was administered in 98.4% of all episodes. Although, there were no fatalities, only 11.4% of patients received prescriptions for self-injectable epinephrine.

Conclusion: The study underscores an increasing trend of anaphylaxis affecting both children and adults in lower northern Thailand, with shrimp and fried insects as common triggers.