Dolichocolon May Differentially Associate with Ulcerative Colitis Phenotype in Children.
BACKGROUND: Dolichocolon (DC) is an underrecognized anatomic variant associated with constipation; its association with ulcerative colitis (UC) is unknown. METHODS: We retrospectively reviewed abdominal MRI and CT scans in children with UC, Crohn's disease (CD), and non-inflammatory bowel disease (non-IBD) controls, classifying DC subtypes. RESULTS: A total of 111 cases (66 with UC) were examined. DC was similarly common (p = 0.4436) in patients with constipated (69%) or non-constipated (NC-UC: 57%) UC. In non-constipated (NC) patients, DC prevalence was higher in children with UC than those with CD or controls. Type 1 DC predominated in NC children with proctitis/left-sided UC (E1/E2), while Type 2 DC was enriched in children with extensive/pancolitis (E3/E4). DISCUSSION: DC may be associated with different phenotypes of UC and may influence disease distribution independent of constipation. However, given the cross-sectional design of this study, these associations should be interpreted cautiously and require confirmation in longitudinal studies.