Overview
Definition
The invagination or 'telescoping' of one segment of the intestine into an adjacent segment, causing mechanical bowel obstruction.
Epidemiology
The most common cause of bowel obstruction in infants aged 6-36 months. M:F ratio ~3:1.
Etiology & Risk Factors
- Idiopathic in 90% of children (associated with lymphoid hyperplasia after viral infection, serving as lead point)
- Pathologic lead point (Meckel's diverticulum, polyp, Henoch-Schönlein purpura) in older children/adults
- Association with rotavirus vaccine
Clinical Symptoms
- Sudden-onset, severe, colicky abdominal pain (infant draws knees to chest and screams) alternating with periods of normal behavior
- Vomiting (initially non-bilious, becomes bilious)
- Classic 'currant jelly' stools (mixed blood and mucus)
- Palpable 'sausage-shaped' mass in the right upper quadrant
- Apathy or lethargy
Clinical Approach
Diagnosis
- Abdominal Ultrasound showing classic 'target' or 'donut' sign in transverse view, and 'pseudokidney' sign in longitudinal view
Management
- Non-operative reduction: Air or contrast (barium/saline) hydrostatic enema under fluoroscopy/ultrasound (highly successful, contraindicated if signs of peritonitis/perforation)
- Surgical reduction or resection if enema fails or perforation is present
Complications
- Bowel perforation / Peritonitis
- Sepsis
- Bowel necrosis