What are the management steps for a 2-year-old who swallowed a magnet that is not visible on x-ray?

Management of Magnet Ingestion in a 2-Year-Old with Negative X-Ray

Proceed immediately to emergent endoscopy (within 2-6 hours) regardless of negative x-ray findings, as magnets require urgent removal due to high risk of pressure necrosis, perforation, and fistula formation. 1

Critical Understanding: Why X-Ray May Be Negative

• Plain radiographs have a false-negative rate up to 47% for foreign body detection, and can miss certain objects entirely 1
• A single small magnet or certain magnet orientations may not be clearly visible on standard x-rays 2
• The absence of radiographic findings does NOT exclude magnet ingestion when history is suggestive 1

Immediate Management Algorithm

Step 1: Obtain CT Scan

• CT scan should be performed immediately as it has 90-100% sensitivity compared to only 32% for plain x-rays 1
• CT will definitively identify the magnet(s), determine exact location, number of magnets, and assess for early complications (perforation, obstruction, fistula formation) 1

Step 2: Emergent Endoscopy (Within 2-6 Hours)

• Emergent flexible endoscopy is mandated for magnet ingestion due to risk of pressure necrosis between magnets or between magnet and other metallic objects 1
• This timeframe applies regardless of whether single or multiple magnets are suspected 1
• Do NOT wait for symptoms to develop—multiple magnets can cause entero-enteric fistula, intestinal necrosis, and perforation even in asymptomatic children 3, 4, 5

Step 3: Surgical Readiness

• If endoscopic retrieval fails or if the magnet has passed beyond the stomach, close surgical monitoring is required 3
• Multiple magnet ingestion (or magnet with other metal) creates magnetic attraction across bowel loops causing pressure necrosis, perforation, and fistula formation within hours to days 3, 4, 5
• Surgical exploration should be performed promptly if magnets are in the small bowel and cannot be retrieved endoscopically, rather than waiting for complications to develop 3, 5

Critical Pitfalls to Avoid

• Never rely on negative x-ray to exclude magnet ingestion when history is positive 1
• Do not use contrast swallow studies—they increase aspiration risk and impair endoscopic visualization 1
• Do not adopt a "wait and see" approach assuming the magnet will pass spontaneously like other foreign bodies—magnets behave differently and cause unique complications 3, 4, 5
• Even a single magnet is dangerous if there is any possibility of multiple magnets or co-ingestion with other metallic objects 1, 3

Specific Complications of Magnet Ingestion

• Magnetic attraction across bowel walls causes pressure necrosis leading to perforation, fistula formation (entero-enteric or jejunocolic), intestinal obstruction, and sepsis 3, 4, 5
• These complications can occur rapidly—case reports document fistula formation and perforation requiring bowel resection in children who ingested 5-62 magnetic beads 3, 6, 4
• Morbidity is significantly higher with magnet ingestion compared to other foreign bodies, with surgical intervention rates approaching 100% when multiple magnets are involved 3, 4, 5

Intraoperative Considerations

• A novel approach using a pacemaker magnet or similar magnetic apparatus can help locate remaining magnetic foreign bodies during surgical exploration 6
• Expect to find edematous, inflamed bowel segments with omega-shaped loops where magnets have attracted across bowel walls 3
• Bowel resection with primary anastomosis is often required rather than simple foreign body removal 3, 4