Pediatrics · Year 3 · from Pediatrics

Case 1: Intussusception

Patient Demographics

  • Age: 9-month-old male
  • Sex: Male

Chief Complaint

"He's screaming in pain and has bloody stool."

History of Present Illness

A 9-month-old previously healthy male presents with episodes of severe crying and drawing up of legs that started 8 hours ago. Parents describe the episodes as sudden onset, with the infant screaming inconsolably for 2-3 minutes, then becoming quiet and appearing tired. The episodes occur approximately every 15-20 minutes. He had one episode of non-bilious vomiting. Between episodes, he has been increasingly lethargic and less interested in feeding. Mother noticed a bowel movement 2 hours ago that looked like "red jelly" mixed with mucus. He had a viral illness with mild diarrhea one week ago that resolved. No fever. This is the first time he has had these symptoms.

Growth Parameters

  • Weight: 9.0 kg (55th percentile)
  • Length: 71 cm (50th percentile)
  • Head circumference: 45 cm (50th percentile)

Physical Examination

  • General: Pale, lethargic between episodes; during episode: inconsolable crying, legs drawn up
  • Vital signs: T 37.2C, HR 145, RR 32, BP 90/55
  • HEENT: Mucous membranes moist, no oral lesions
  • Cardiovascular: Tachycardia, no murmur
  • Abdomen:
  • Soft between episodes
  • Palpable sausage-shaped mass in right upper quadrant
  • Right lower quadrant feels "empty" (Dance sign)
  • Mild distension
  • No peritoneal signs
  • Rectal: "Currant jelly" stool - bloody mucus on examiner's finger
  • Skin: Pale, delayed capillary refill (3 seconds)
  • Neurologic: Lethargic, but arousable

Workup

  • Abdominal X-ray: Paucity of gas in right lower quadrant, soft tissue mass in right upper quadrant, no free air
  • Abdominal ultrasound: "Target sign" - concentric rings representing bowel-within-bowel in right abdomen; no free fluid
  • CBC: WBC 14,000, Hgb 11.2, Platelets 320,000
  • CMP: Na 138, K 4.5, BUN 18 (mild dehydration), Cr 0.3

Diagnosis

Ileocolic intussusception

Clinical Reasoning

The classic triad of colicky abdominal pain (paroxysmal crying with legs drawn up), "currant jelly" stool (blood and mucus), and palpable abdominal mass (sausage-shaped) in a child 6-36 months is pathognomonic for intussusception. The preceding viral illness is a common antecedent, thought to cause lymphoid hyperplasia serving as a lead point. The lethargy between episodes is a concerning sign of progression. Ultrasound confirmation with the "target sign" is diagnostic and preferred over barium enema for initial imaging.

Management

  1. NPO and IV access: Normal saline bolus 20 mL/kg for resuscitation
  2. Pediatric surgery consultation (obtain early)
  3. Air enema reduction (therapeutic):
  • Gold standard for uncomplicated intussusception
  • Performed under fluoroscopy by pediatric radiologist
  • Success rate 80-90% on first attempt
  • Contraindications: peritonitis, perforation, shock
  1. If air enema unsuccessful:
  • Second attempt can be considered after 30-60 minutes
  • Maximum 3 attempts
  1. Surgical intervention indicated for:
  • Failed enema reduction
  • Perforation or peritonitis
  • Hemodynamic instability
  • Pathologic lead point suspected (Meckel's, polyp, lymphoma)
  1. Post-reduction:
  • Observe 12-24 hours for recurrence
  • Resume feeds when tolerating clear liquids
  • Recurrence rate 5-10% (higher with multiple reductions)
  1. Discharge instructions:
  • Return for recurrent symptoms (recurrence most common within 72 hours)

Clinical Image

Image Description: Ultrasound image demonstrating the "target sign" of intussusception - concentric rings representing the telescoped bowel-within-bowel.

Source: Radiopaedia URL: https://radiopaedia.org/cases/intussusception-target-sign License: CC BY-NC-SA 3.0

All cases for this lecture as Markdown