In a 15‑month‑old infant with 12 hours of abdominal pain, vomiting, bloody mucous stool, pallor, hyperactive bowel sounds, and an obstructive pattern on abdominal radiograph, what is the most important next step in management?

Management of Suspected Intussusception in a 15-Month-Old Infant

The most important step in management is barium enema (or air/saline enema), which serves both diagnostic and therapeutic purposes in this clinical scenario highly suggestive of intussusception. 1, 2, 3

Clinical Presentation Analysis

This 15-month-old presents with the classic features of intussusception:

• Abdominal pain with apparent discomfort – the hallmark symptom occurring in 100% of cases 4
• Vomiting – present in approximately 82% of intussusception cases 4
• Bloody mucous per rectum ("currant jelly" stools) – indicates mucosal damage and is a concerning feature specific to intussusception 1, 2
• Pallor – suggests blood loss and progression of the condition 5
• Hyperactive bowel sounds – consistent with early obstruction 1
• Obstructive pattern on abdominal film – confirms intestinal obstruction 1, 2

The age of 15 months falls within the peak incidence range (most common between 6-18 months, with median age 9-12.5 months) 1, 4, 5

Why Barium/Air Enema is the Answer

Pneumatic (air) or hydrostatic (barium/saline) enema is both diagnostic AND therapeutic, with success rates exceeding 90-98% when performed early 3, 4:

• Diagnostic confirmation: The enema definitively confirms intussusception by visualizing the intussusceptum 3, 6
• Therapeutic reduction: Non-surgical reduction (NSR) via enema successfully reduces intussusception in over 90% of cases, avoiding surgery 3, 4
• Time-sensitive efficacy: Early intervention (within 24 hours) dramatically improves success rates – 80.5% of successful cases presented within 24 hours 4
• Lower morbidity: Patients treated with pneumatic reduction have median hospital stays of 2 days versus 6 days for surgical cases 4

Why Other Options Are Incorrect

A. Bowel Rest and IV Hydration Alone

• While supportive care is necessary, it does not address the underlying mechanical obstruction 1, 2
• Intussusception requires active reduction – the bowel will not spontaneously reduce with conservative management alone 3, 6
• Delayed treatment increases risk of bowel necrosis, perforation, and need for surgical resection 4, 5

B. Intravenous Antibiotics

• Antibiotics have no role in uncomplicated intussusception 1
• They would only be indicated if perforation or peritonitis develops, which are contraindications to enema reduction 3, 6

C. Immediate Surgery

• Surgery is reserved for failed enema reduction, signs of perforation, shock, or peritonitis 3, 6
• With an 80-98% success rate for enema reduction, attempting NSR first avoids unnecessary laparotomy 3, 4
• Immediate surgery without attempting enema reduction exposes the patient to higher morbidity (longer hospital stay, surgical complications) 4

Critical Management Algorithm

Step 1: Immediate stabilization

• IV fluid resuscitation for dehydration and pallor 1
• NPO status (bowel rest as supportive measure, not definitive treatment) 1

Step 2: Confirm diagnosis with imaging

• Ultrasound has 98-100% sensitivity and 100% negative predictive value 3
• Plain abdominal radiograph already shows obstructive pattern 1, 2

Step 3: Proceed directly to therapeutic enema

• Air enema under fluoroscopy or saline enema under ultrasound guidance 3
• Success rate 90-98% when performed early 3, 4
• First attempt has highest success; subsequent attempts have reduced efficacy 5

Step 4: Surgery only if enema fails or contraindications exist

• Contraindications to enema: perforation, shock, peritonitis 3, 6
• If enema unsuccessful, proceed to surgical reduction ± bowel resection 4, 5

Critical Pitfalls to Avoid

• Do not delay definitive treatment: Every hour of delay increases risk of bowel necrosis and need for resection 4, 5
• Do not rely on the "classic triad": Only 46-66% of patients present with all three classic features (pain, vomiting, bloody stools) 4, 5
• Do not assume bloody stools must be present: Only 11.9% in one series had bloody stools at presentation, yet all had confirmed intussusception 4
• Do not perform immediate surgery without attempting enema reduction unless clear contraindications exist (perforation, peritonitis, shock) 3, 6, 4

The patient in this scenario has NO contraindications to enema reduction (no signs of perforation, shock is not mentioned, and the infant is only "slightly pale"), making therapeutic enema the most appropriate next step 3, 6.