What is intussusception?

Intussusception: Definition, Diagnosis, and Management

Intussusception is defined as the invagination of one segment of the bowel into an immediately adjacent segment of the bowel, which can lead to intestinal obstruction and requires prompt diagnosis and management. 1, 2

Clinical Presentation

Pediatric Presentation

• Uncommon in the first 3 months of life
• Typically presents with crampy, intermittent abdominal pain
• May progress to bloody stools and lethargy
• Most commonly idiopathic and ileocolic in children 1

Adult Presentation

• Rare cause of intestinal obstruction (1-5% of all bowel obstructions)
• Symptoms often include:
  • Abdominal pain (chronic or acute)
  • Nausea and vomiting
  • Signs of intestinal obstruction
• May present as chronic, intermittent, or acute condition 3, 4
• Unlike children, adult intussusception is usually associated with a lead point pathology 2

Anatomical Classification

• Small Bowel Intussusception:

  • Jejunojejunal
  • Ileoileal
  • Ileocolic
  • More common in adults (85% of cases) 3
  • Usually associated with benign lead points when pathology is present 2

• Colonic Intussusception:

  • Colocolic
  • Less common in adults (15% of cases) 3
  • Higher association with malignancy 3

• Gastroduodenal Intussusception:

  • Presents with epigastric pain, nausea, vomiting
  • May have palpable epigastric mass
  • Signs of gastric outlet obstruction 1

Diagnostic Approach

1. Initial Imaging:

   • Abdominal plain X-ray should be performed first
   • Diagnostic in 50-60% of bowel obstruction cases
   • Helps determine presence and level of obstruction 1

2. Advanced Imaging:

   • CT scan is preferred for gastroduodenal intussusception
   • Ultrasound may suggest intussusception
   • Endoscopy can identify potential lead points (tumors/polyps) 1
   • Cross-sectional imaging increasingly identifies transient/asymptomatic intussusceptions that may be observed without intervention 2

Management

Initial Management

• Immediate intravenous crystalloid fluid resuscitation
• Nasogastric tube insertion for decompression
• Anti-emetics as needed
• Foley catheter placement to monitor urine output
• Proton pump inhibitors for gastroduodenal disease
• Appropriate antibiotic therapy based on patient classification 1

Surgical Management

Pediatric Cases:

• Typically managed with non-operative reduction via pneumatic/hydrostatic enemas 2

Adult Cases:

• Surgical intervention is necessary in all symptomatic cases 4
• Approach determined by patient's hemodynamic status, underlying cause, and presence of complications 1
• Options include:
  • Laparoscopic or open surgical reduction for stable patients
  • Open surgical approach for unstable patients
  • Damage control procedure for severe hemodynamic instability 1

Resection Considerations:

• In small bowel intussusception: Reduction can be attempted if segment is viable and malignancy not suspected
• In colonic intussusception: More careful approach due to higher risk of malignancy
• Resection of non-viable segments and underlying lesions is often required 1, 3
• Delay in surgical intervention beyond 48 hours significantly increases mortality 1

Important Distinctions Between Adult and Pediatric Intussusception

Feature	Pediatric	Adult
Frequency	More common	Rare
Etiology	Usually idiopathic	Usually has lead point pathology
Location	Primarily ileocolic	Primarily small intestine
Management	Often non-operative	Usually surgical
Malignancy risk	Low	High, especially in colonic cases

Pitfalls and Caveats

• Adult intussusception is often a preoperative diagnostic challenge due to variable and non-specific symptoms 3
• Transient intussusceptions found incidentally on imaging may not require intervention 2
• Reduction without resection in adults carries risk if malignancy is present, especially in colonic intussusception 3
• Laparoscopy offers both diagnostic and therapeutic options in stable patients 4
• In post-bariatric surgery patients, intussusception should be considered as a potential cause of small bowel obstruction 5