Short bowel syndrome (SBS)

Short bowel syndrome (SBS) is (1,3)

• a functional definition of SBS is necessary due to the wide variation in small bowel length in adults (300-800 cm) and the ability of the remaining bowel to compensate for the lost length
  • therefore SBS is defined as the inability to maintain nutritional, fluid, and/or electrolyte homeostasis while consuming a normal, healthy diet following a bowel resection
  • caused by physical or functional loss of significant portions of the small intestine
    • physical loss - in adults, usually result from extensive intestinal resection for recurrent Crohn's disease, mesenteric vascular events (eg, embolism, thrombus), trauma, volvulus, malignancy, and complications from previous abdominal surgery
    • functional loss - less common
      • occur in the presence of an intact small intestine that is not adequately performing its normal digestive and absorptive functions
      • causes include inflammatory bowel disease, radiation enteritis, recurrent intestinal pseudo-obstruction, and congenital villus atrophy
  • conditions leading to SBS most frequently affect the jejuno-ileal segment, although the colon may also be affected
• clinical features of SBS vary along a continuum, depending on the extent and anatomy of intestine lost and the ability of the patient and the remaining intestine to compensate for the loss
  • clinical complications associated with SBS include:
    • central venous catheter-related complications e.g. infection, occlusion, thrombosis
    • parenteral nutrition–related e.g. hepatic complications (steatosis, cholestasis, fibrosis, cirrhosis); gallstones
    • bowel anatomy–related e.g. malabsorptive diarrhoea, malnutrition, fluid and electrolyte disturbances
      
• in patients with SBS who are receiving long-term home parenteral nutrition (PN)
  • 2- and 5-year survival rates have been reported to be up to 80% and 70%, respectively (2)
• factors affecting survival with SBS include: (3)
  • the anatomy and function of the remaining bowel,
  • age of the patient,
  • primary disease process,
  • comorbid diseases,
  • presence of chronic intestinal obstruction,
  • and the experience of the management team

Reference

1. Pironi L, Arends J, Baxter J, et al. ESPEN endorsed recommendations. Definition and classification of intestinal failure in adults. Clin Nutr. 2015 Apr;34(2):171-80.
2. Scolapio JS, Fleming CR, Kelly DG, Wick DM, Zinsmeister AR. Survival of home parenteral nutrition-treated patients: 20 years of experience at the Mayo Clinic. Mayo Clin Proc. 1999;74(3):217-222.
3. Massironi S, Cavalcoli F, Rausa E, et al. Understanding short bowel syndrome: current status and future perspectives. Dig Liver Dis. 2020 Mar;52(3):253-61.