What is the recommended diagnostic work‑up and management for adult large‑bowel intussusception?

Management of Adult Large Bowel Intussusception

Adult large bowel intussusception requires CT scan for diagnosis followed by surgical exploration with resection in nearly all cases, as 86-93% harbor an underlying pathological lead point (most commonly malignancy), making non-operative reduction inappropriate. 1, 2

Diagnostic Work-Up

Imaging

• CT scan with intravenous contrast is mandatory as the diagnostic modality of choice, with sensitivity of 80% and specificity near 100% for identifying intussusception, the lead point, and complications such as ischemia or perforation 3, 2, 4, 5
• Look specifically for: pneumatosis intestinalis, free intraperitoneal air, closed-loop obstruction, and bowel wall thickening with poor enhancement—all of which mandate emergency surgery 6
• Plain radiographs and ultrasound are inadequate and should not delay CT imaging 6

Clinical Assessment

• Evaluate for signs of peritonitis (guarding, rigidity, rebound tenderness, absent bowel sounds) which necessitate immediate surgical intervention 1, 2
• Assess for bowel ischemia indicators: fever, tachycardia, confusion, lactic acidosis, leukocytosis, markedly elevated lactate, severe continuous pain, or bloody stools 1, 6
• Check hemodynamic stability—hypotension despite resuscitation mandates emergency surgery 1, 2

Initial Stabilization

Before surgery, perform:

• IV crystalloid resuscitation to correct dehydration and electrolyte imbalances 6
• Nasogastric tube decompression (supportive only, does not reduce intussusception) 1, 6
• Foley catheter to monitor urine output 6
• Broad-spectrum antibiotics once intussusception is diagnosed or suspected 2, 6
• Obtain surgical consultation immediately in all cases 2

Surgical Management

Primary Treatment Approach

Surgical exploration with resection (without reduction) is the recommended primary treatment for the following reasons:

• 86-93% of adult large bowel intussusceptions have a definable pathological lesion, with colonic lesions being predominantly malignant (adenocarcinoma most common) 1, 2, 4, 5
• High risk of incarceration and strangulation 2
• Delays beyond 48 hours significantly increase mortality 1, 2

Surgical Technique

• Perform resection without attempting reduction when malignancy is suspected or the etiology is uncertain, as manipulation may cause tumor seeding 4, 5
• For right-sided lesions: right hemicolectomy with primary anastomosis 3, 4
• For left-sided malignant lesions: resection with primary anastomosis in stable patients without perforation 3, 6
• For high-risk patients or those with perforation: staged procedure (e.g., Hartmann procedure) 3, 6
• Close all mesenteric defects with non-absorbable sutures after reduction to prevent recurrence 2

Special Considerations for Benign Lead Points

• If a benign cause (lipoma, fibroma, Meckel's diverticulum) is confidently identified preoperatively, reduction may be considered only if there are no signs of ischemia 5, 7, 8
• However, since the etiology is often uncertain preoperatively, the lesion must be interpreted as malignant and extensive resection is recommended 5
• Laparoscopic approach may be considered for confirmed benign small bowel intussusception, though this is rarely applicable to large bowel cases 7

Non-Operative Management

Non-operative management is NOT recommended for adult large bowel intussusception due to:

• The extremely high rate of underlying malignancy (86-93%) 1, 2
• High recurrence risk with endoscopic reduction 2
• Risk of delaying definitive treatment for cancer 4, 5

The only exception is highly selected cases meeting ALL of the following criteria:

• Hemodynamically stable with no signs of peritonitis or bowel compromise 2
• Endoscopic expertise readily available 2
• Close monitoring for at least 24 hours after reduction 1, 2

Critical Pitfalls to Avoid

• Never delay surgery beyond 48 hours, as this significantly increases mortality 1, 2, 6
• Do not attempt reduction when malignancy is suspected, as this may cause tumor seeding and worsen oncologic outcomes 4, 5
• Do not rely on the classic pediatric triad (vomiting, abdominal pain, passage of blood per rectum), as adult intussusception rarely presents this way 4
• Do not assume benign etiology even if imaging suggests lipoma—colonic intussusceptions are predominantly malignant and require oncologic resection 4, 5, 8

Prognosis

• Overall mortality for large bowel obstruction ranges from 11-22% depending on whether primary anastomosis is performed versus staged procedures 6
• Recurrence after surgical reduction occurs in 0.1-0.3% of cases, with highest risk in the first 10 days postoperatively 2
• Prognosis is better when there is a benign lead point, but these represent only 7-14% of adult large bowel intussusception cases 1, 2, 8