Description

• Invagination (telescoping) of a portion of intestine into itself
  • May involve any part of small intestine or ileocolic (95%) or colocolic segment
• System(s) affected: gastrointestinal (GI)

Geriatric Considerations

• 5% of all intussusceptions occur in adults.
• <5% of intestinal obstruction cases in adults are due to intussusception.
• 90% of adult cases have pathologic lead point.

Pediatric Considerations

• Most common abdominal emergency in infancy
• Most are idiopathic ileocolic intussusceptions; pathologic lead point identified only in 2–12%
• Postoperative intussusception (1 to 24 days postoperatively) typically involves the small bowel and is difficult to reduce hydrostatically.

Epidemiology

Incidence: 30 per 100,000 infants annually in the United States

• Predominant age
  • 5 to 10 months (~65% are <1 year of age)
  • Only 10–25% of cases occur after 1 year of age.
• Predominant sex: male > female (3:2). Male preponderance is more obvious in older infants.

Etiology and Pathophysiology

• Children
  • Marked hypertrophy of Peyer patches: 92–98%
  • Lead point in 2–12%
    • Meckel diverticulum, duplication cyst, aberrant tissue, intestinal polyp, ectopic pancreas, lymphoma, Henoch-Schönlein purpura as causes of pathologic lead point (if identified)
  • Allergic reactions, diet changes, and changes in intestinal activity may be contributory.
  • Idiopathic intussusceptions commonly associated with preceding adenovirus infection (24–40%)
  • 1/10,000 to 1/32,000 vaccinated children developed intussusception with previous versions of rotavirus vaccine which has been withdrawn.
  • Safety and efficacy trials of newer rotavirus vaccines (RV1 [Rotarix] and RV5 [RotaTeq]) show minimal intussusception risk (5.3 per 100,000 infants with RV1 and 1.5 excess cases of intussusception per 100,000 with RV5).
• Adults: Pathologic lead point is typical.
  • Neoplasm in 70% of adult intussusceptions
  • Intussusception of small bowel is usually caused by benign neoplasms; large bowel is usually caused by malignant neoplasms.
  • Any syndrome with polyp or hamartoma (i.e., Peutz-Jeghers syndrome, Cowden syndrome) can provide a lead point.

Risk Factors

• Age (<1 year of age)
• Recent upper respiratory tract infection (24–40%)
• Recent operation (1 to 24 days previously)
• Recent viral GI illness
• Meckel diverticulum
• Recent operative procedure
• Intestinal polyp or neoplasia

Commonly Associated Conditions

• Henoch-Schönlein purpura
  • Intussusception is a rare but well-recognized complication.
• Cystic fibrosis
  • Intussusceptions occur in ~1% of cystic fibrosis patients.
• Lymphoma (rare)
• Polyps (rare)
• Small bowel carcinoma
• Peutz-Jeghers syndrome