Cutoffs and Characteristics of Abnormal Bowel Dilatation in Pediatric Short Bowel Syndrome

Abstract

Objectives: Although excessive intestinal dilatation associates with worsened outcomes in pediatric short bowel syndrome (SBS), little is known about the natural history and definition of pathological dilatation. We addressed fore-, mid-, and hind-gut dilatation in children with SBS, who had not undergone autologous intestinal reconstructive (AIR) surgery, in relation to controls. Methods: SBS children without history of AIR surgery (n = 59) and age-matched controls without any disclosed intestinal pathology (n = 140) were included. Maximum diameter of duodenum, small bowel (SB), and colon were measured in each intestinal contrast series during 2002 to 2020 and expressed as diameter ratio (DR) to L5 vertebrae height. Predictive ability of DR for weaning off parenteral nutrition (PN) was analyzed with Cox proportional hazards regression models using multiple cutoffs. Results: Duodenum (DDR), SB (SBDR), and colon (CDR) DR were 53%, 183%, and 23% higher in SBS patients compared to controls (P < 0.01 for all). The maximal DDR and SBDR measured during follow-up is associated with current PN dependence and young age. DDR correlated with SBDR (r = 0.586, P < 0.01). Patients with maximal DDR less than 1.5, which was also the 99th percentile for controls, were 2.5-fold more likely to wean off PN (P = 0.005), whereas SBDR and CDR were not predictive for PN duration. Conclusions: All segments of remaining bowel, especially SB, dilate above normal levels in children with SBS. In SBS children without AIR surgery, PN dependence and young age is associated with duodenal and small intestinal dilatation, while duodenal dilatation also predicted prolonged PN.