Intussusception



Background

  • Intussusception is the invagination of a proximal segment of bowel into the distal bowel lumen
  • The commonest occurrence is a segment of ileum moving into the colon through the ileo-caecal valve
  • Any age but commonly in the 2 month to 2 years (peak 5 to 9 months)
  • M:F = 2:1

History

  • Intermittent severe, colicky (child drawing up the legs)
  • Episodes 2-3 times/hour and may increase over the next 12-24 hours
  • During these episodes of crying the child may look pale (note: many other causes of infant crying are associated with facial redness rather than pallor)
  • Pallor & lethargy may be the predominant or persistent rather than episodic, and in some the crying episodes may not be very vigorous
  • Vomiting usually prominent (bilious vomiting late)
  • Bowel motions
    • Blood and/or mucus
    • Classic red currant jelly stool is a late sign
  • Diarrhoea is common and can lead to a misdiagnosis of gastroenteritis
  • There may be a preceding respiratory or diarrhoeal illness

Examination

  • Pallor, lethargy - may be intermittent, and may look well in between episodes
  • Abdominal mass - sausage shaped mass RUQ or crossing midline in epigastrium or behind the umbilicus, palpable in ⅔ of children
  • Distended abdomen later
  • Stool:
    • Bloody stool/occult blood positive
    • PR unnecessary if good evidence of intussusception; abdominal mass or PR bleeding, but otherwise should be done for signs of PR blood or mass
  • Signs of an acute bowel obstruction
  • Hypovolaemic shock is a late sign

Investigations

Plain abdominal X-ray

  • Performed to exclude perforation or bowel obstruction
  • A normal AXR does not exclude intussusception

Signs of intussusception on a plain Xray include:

  • Target sign - 2 concentric circular radiolucent lines usually in the RUQ
  • Crescent sign - lucency usually in the LUQ with a soft tissue mass

Gas insufflation enema (or contrast enema)

  • Diagnostic investigation of choice if high level of suspicion
  • This intervention is both diagnostic and therapeutic

Ultrasound

  • Useful if suggestive Hx but no mass palpable or signs on plain AXR

Labs

  • Blood glucose
  • Blood group and hold prior to theatre
  • FBE and U&E may be useful if child looks unwell
Target sign Target sign

Management

  • If shocked see resuscitation guidelines
  • Involve surgeons early
  • Secure IV access:
    • Most require resuscitation with NS 20mls/kg IV
  • Keep nil orally
  • Pass NG tube if bowel obstruction on AXR
  • In general:
    • Ilioileal intussusception = treat conservative
    • Iliocaecal = intervention


Content by Prof.Ronán O' Sullivan, Dr Íomhar O' Sullivan 2/07/2007. Last review Dr IOS 25/04/24.