Intussusception

Snapshot

  • A 3-year-old boy is brought to the emergency room because of bloody stool and abdominal pain. His parents reveal that he recently had an episode of gastroenteritis, likely picked up in his day care. However, since his gastroeneteritis resolved, he has been doing well until this morning, when he complained of pain and clutched his tummy. An hour later, he had an episode of red/purple jelly-like stool. An ultrasound reveals a target-like shape.

Introduction

  • Bowel obstruction
  • Segment of bowel invaginating or telescoping into another part of the bowel
  • Epidemiology    
    • most common in children < 5 years old
  • Pathogenesis
    • 90% unknown causes
      • some attributed to rotavirus gastroenteritis
        • hyperplasia of Peyers patches 
    • 5% pathological lead point, typically in older children or adults
      • Meckel diverticulum
      • cysts
      • polyps
      • lymphoma
      • HSP
      • Peutz-Jeghers syndrome
  • Most often ileo-colic

Presentation

  • Symptoms
    • sudden intermittent abdominal pain
    • “currant jelly” stools
      • mucus/blood
    • bilious vomiting
    • child may flex knees to chest to relieve pain
  • Physical exam
    • may feel abdominal mass in RUQ
      • sausage-shaped, oblong
    • may have abdominal distension
  • guaiac positive stool

Evaluation

  • Imaging
    • abdominal ultrasound
      • target or donut sign
    • abdominal radiography
      • may have air fluid levels
      • not diagnostic
    • air or barium enema
      • coil-spring sign
  • therapeutic

Differential Diagnosis

  • Midgut volvulus 
  • Intestinal atresia
  • Gastroenteritis
  • Appendicitis 
  • Meckel diverticulum 

Treatment

  • Non-surgical intervention
    • bariuma or air enema
      • observe 24 hours for recurrence or complications
  • Surgical reduction
    • only indicated if enema fails
  • appendix often removed to prevent future confusion between appendicitis and intussusception

Prognosis, Prevention, and Complications

  • Prognosis
    • very good with treatment
    • may spontaneously reduce but often needs reduction by enema or surgery
  • Complications
    • risk of recurrence
    • bowel necrosis
    • perforation
    • sepsis