Background: Few studies have assessed the incidence of eosinophilic esophagitis (EoE) in childhood. Our study aimed to determine the incidence of EoE in pediatric patients undergoing upper gastrointestinal endoscopy (UGE), with analysis of epidemiological data including sex, age, symptoms, frequency of atopy, and endoscopic and histological findings.
Methods: We performed a retrospective, observational, analytical study of the medical records of patients aged 0 to 14 years who underwent UGE in a tertiary hospital from January 2004 to January 2014.
Results: A total of 4071 upper digestive endoscopies were performed in 2651 patients. Esophageal eosinophilia was found in 405 biopsy reports, and 127 patients had ≥15/HPF. The clinical histories of 70 patients were analyzed. Sixty-three fulfilled the diagnostic criteria for EoE, 3 fulfilled the criteria for eosinophilic gastroenteritis, and 4 cases were secondary to caustic ingestion. The mean annual incidence was 2.48/100 000 individuals/year and the cumulative incidence over 10 years was 24.8/100 000. No statistical differences were found between responders to proton pump inhibitors and nonresponders for age, gender, atopic diseases, symptoms, and endoscopy findings.
Conclusion: The incidence of EoE in the present study was similar to that reported in the literature. However, these data may be underestimated owing to difficulties accessing UGE. Increased knowledge of esophageal eosinophilic diseases in childhood requires associated improvements in health infrastructure.

Key words: Eosinophilic esophagitis, Proton pump inhibitor responsive esophageal eosinophilia, Atopic diseases, Childhood, Prevalence