Introduction: Tapering surgery of dilated small bowel (SB) may facilitate weaning from parenteral nutrition (PN) and improve deteriorated liver function in short bowel syndrome (SBS). However, the effects of tapering on bloodstream infections (BSIs), liver biochemistry, mucosal integrity markers, and cholesterol metabolism remain largely unknown.

Methods: Among 17 SBS children having undergone tapering surgery (serial transverse enteroplasty, n=12; Bianchi, n=2; simple tapering or resection, n=3), we retrospectively analyzed the frequency of BSIs, liver biochemistry, plasma citrulline and fecal calprotectin – respective markers of mucosal mass and inflammation, as well as concentrations of plasma lipids and serum cholesterol precursors – markers of body cholesterol synthesis – before and after surgery. Maximal SB diameter was measured in contrast series and expressed as ratio to fifth lumbar vertebra height (SB diameter ratio).

Results: SBS was due to SB atresia (n=9), midgut volvulus (n=4), necrotizing enterocolitis (n=3), or gastroschisis (n=1). Median length of remaining small bowel (SB) was 30 (interquartile range 18-41) cm and age at tapering 15.9 (7.3-64.0) months. SB diameter ratio decreased after surgery (Table 1) and correlated negatively with serum total cholesterol (r=-0.400, p=0.021), HDL (r=-0.404, p=0.020), and citrulline (r=-0.546, p=0.004) while positively with plasma aminotransferases (r=0.331-0.497, p<0.001-0.007) and bilirubin (r=0.277, p=0.026). Postoperatively, parenteral energy requirement decreased in all patients and after a follow-up of 3.14 (1.4-8.72) years, 71% were off PN. After surgery, the frequency of both all BSIs and those of intestinal origin decreased significantly; fecal calprotectin decreased to normal range; bilirubin and aspartate aminotransferase decreased; while citrulline remained unchanged (Table 1). Serum high-density lipoprotein normalized and the elevated concentrations of cholesterol precursors; cholestenol, desmosterol, and lathosterol decreased after surgery; denoting improved cholesterol/bile acid absorption (Table 2).

Conclusion: In addition to reducing the need for PN, tapering surgery in SBS children reduces BSIs, improves markers of liver function and mucosal inflammation, and, as suggested by decreased cholesterol precursor levels, may improve intestinal absorption of cholesterol/bile acids. SB diameter ratio in children likely reflects the degree of bowel dilatation more reliably than absolute SB width.