Short bowel syndrome

Short bowel syndrome is a malabsorptive condition caused by the surgical removal of a significant portion of the small intestine. Clinical features include chronic diarrhea, dehydration, weight loss, and electrolyte abnormalities. Diagnosis is confirmed by a comprehensive nutritional assessment in patients with an estimated residual small bowel length ≤ 200 cm. Nutritional management involves individualized dietary modifications, fluid management with oral rehydration solutions, and specialized nutrition support. Pharmacological treatments include antidiarrheals, antisecretory agents, and agents to support absorption (e.g., teduglutide). Complications can arise from the condition itself or from treatment; complications include catheter-related infections, metabolic bone disease, and kidney stones.

A syndrome of malnutrition caused by significant surgical resection of the small intestine, which results in an inability to absorb the necessary macronutrients, water, and electrolytes needed to maintain homeostasis despite adequate nutritional intake. ^[1][2]

• US prevalence: ∼ 3 million people ^[2]
• Worldwide prevalence: ∼ 0.12–2.74 per 100,000 people ^[2]

Epidemiological data refers to the US, unless otherwise specified.

• Short bowel syndrome is caused by the surgical resection of a significant portion of the small bowel. ^[2]
• Common underlying conditions leading to resection include: ^[2]
  • Mesenteric ischemia
  • Crohn disease
  • Malignancy

• Common signs and symptoms ^[1]
  • Chronic diarrhea
  • Dehydration
  • Electrolyte abnormalities
  • Weight loss
• Consequences of terminal ileum resection, e.g.: ^[1]
  • Vitamin B₁₂ deficiency
  • Bile acid diarrhea

• Consider short bowel syndrome in patients with a post-surgical estimated small bowel length ≤ 200 cm. ^[1]
• Confirmed with a comprehensive nutritional assessment performed by a registered dietitian ^[1]

See "Differential diagnoses of malabsorption."

The differential diagnoses listed here are not exhaustive.

The management of short bowel syndrome is applicable to patients with other causes of chronic intestinal failure.

• Multidisciplinary management, including intestinal rehabilitation ^[1]
• Diet optimization under specialist guidance
  • Frequent meals (e.g., 5–6 meals per day)
  • Recommended diet depends on anatomy (e.g., whether the colon is intact).
  • Consider oral rehydration solutions. ^[1]
  • Total parenteral nutrition may be necessary immediately after bowel surgery and in patients with intestinal failure.
• Pharmacological treatment
  • Antidiarrheal agents (e.g., loperamide)
  • Antisecretory agents to counteract gastric acid hypersecretion (e.g., PPIs, H₂ receptor blockers) ^[1]
  • Agents to support absorption (e.g., glucagon-like peptide 2, teduglutide) ^[1]
• Monitoring for nutritional deficiencies and complications (e.g., intestinal failure) ^[1]
• Surgical management is reserved for advanced disease (e.g., intestinal failure-associated liver disease). ^[3]
  • Autologous gastrointestinal reconstructive surgery
  • Intestinal transplantation

Patients without a functional colon often lose large amounts of water, increasing the risk of dehydration, electrolyte abnormalities, and acute kidney injury. ^[1]

• Central venous catheter infection, occlusion, and thrombosis ^[1]
• Hepatobiliary complications (e.g., steatosis, cholestasis, intestinal failure-associated liver disease) ^[1][3][4]
• Metabolic bone disease (e.g., osteoporosis, osteopenia, osteomalacia) ^[1]
• Kidney impairment (e.g., kidney stones due to hyperoxaluria) ^[4]
• D-lactic acidosis (rare) ^[2]

We list the most important complications. The selection is not exhaustive.

• Intestinal adaptation of the residual bowel occurs within the first 2–3 years after resection, resulting in increased intestinal surface area. ^[2]
  • Within 5 years of diagnosis, over 50% of adults with short bowel syndrome can be weaned completely from parenteral nutrition. ^[1]
  • If weaning from parenteral nutrition is not achieved within the first 2 years after the last bowel resection, the probability of ever weaning is < 6%. ^[1]