Prevalence of Inflammatory Bowel Disease Unclassified, as Estimated Using the Revised Porto Criteria, among Korean Pediatric Patients with Inflammatory Bowel Disease.

This study is the first in Korea to estimate the prevalence of pediatric IBDU. This prevalence (13.1%) aligns with findings from Western studies. Large-scale prospective multicenter studies on PIBDU are required to examine the clinical features and outcomes of this condition.