Can a metal foreign body ingestion cause intussusception in a 6-year-old female with no significant past medical history?

Can an Ingested Metal Foreign Body Cause Intussusception in a 6-Year-Old Female?

Yes, an ingested metal foreign body can cause intussusception in a 6-year-old, though this is an uncommon complication that typically occurs when the foreign body acts as a lead point for bowel telescoping. 1

Mechanism and Risk Factors

• Intussusception can develop when a foreign body becomes lodged in the small bowel and serves as a pathological lead point, causing the proximal bowel to telescope into the distal segment 1
• Metal objects are more likely to cause complications when they are sharp, elongated, or multiple, as these characteristics increase the risk of impaction, perforation, and secondary complications including intussusception 2, 3
• Magnetic foreign bodies pose particular danger when multiple magnets or a magnet plus metallic object are ingested, as they can attract across bowel loops causing pressure necrosis, perforation, and potentially intussusception 2, 4

Clinical Presentation to Anticipate

• Classic intussusception symptoms include crampy abdominal pain, bloody "currant jelly" stools, and progression to bilious vomiting if obstruction develops 1
• In a 6-year-old with foreign body ingestion, suspect intussusception if the child develops episodic colicky pain, vomiting (especially if bilious), abdominal distension, or changes in stool pattern 1, 5
• Physical examination should assess for a palpable abdominal mass, signs of peritonitis, and hemodynamic stability 6

Diagnostic Approach

• Plain radiographs (neck, chest, and abdomen in two views) are the initial screening tool to identify radiopaque metallic objects, assess location, size, shape, and detect signs of perforation or obstruction 6
• Handheld metal detectors have limited utility with sensitivity of only 63.2% overall (79.5% for coins but only 25.5% for batteries and 56% for other metal objects), making them unreliable for excluding metal foreign body ingestion 7, 8
• CT scan should be performed if there is suspicion of complications including perforation, obstruction, or intussusception, as CT has 90-100% sensitivity for detecting foreign bodies and associated complications 6
• Ultrasound may be useful if intussusception is specifically suspected, as it can identify the characteristic "target sign" of telescoped bowel 5

Management Algorithm

If Foreign Body is Identified Without Complications:

• 80% of ingested foreign bodies that reach the stomach will pass spontaneously through the gastrointestinal tract without intervention 3
• Monitor clinically and consider serial radiographs to confirm passage, particularly for sharp or elongated metal objects 6, 3

If Complications are Suspected:

• Obtain CBC, CRP, lactate, and inflammatory markers to assess for systemic illness, perforation, or ischemia 6
• Emergency endoscopic removal is indicated for sharp objects in the esophagus or stomach, multiple magnets, or any foreign body causing symptoms 6, 2
• Surgical consultation is mandatory if there are signs of perforation (fever, peritonitis, free air), obstruction, or intussusception that fails reduction 6

Specific to Intussusception:

• If intussusception is confirmed, attempt pneumatic or hydrostatic reduction as first-line treatment in hemodynamically stable patients without peritonitis 1
• Surgical intervention is required if reduction fails, if there are signs of perforation or necrosis, or if the foreign body cannot be retrieved endoscopically 6, 1

Critical Pitfalls to Avoid

• Do not rely on handheld metal detectors to exclude foreign body ingestion, as they miss 37% of metallic objects overall and 74% of batteries 7, 8
• Do not assume all metal objects will pass spontaneously—sharp objects, magnets, and batteries require closer monitoring and often intervention 2, 3
• Do not delay imaging if the child develops bilious vomiting, as this is a surgical emergency requiring immediate evaluation for malrotation, volvulus, or intussusception 1, 5
• Multiple magnetic objects or a magnet with other metal objects require urgent endoscopic removal even if asymptomatic, as they can cause pressure necrosis across bowel loops leading to perforation or intussusception 2, 4
• Pre-existing intestinal disease or prior abdominal surgery increases complication risk, warranting lower threshold for intervention 3

Bottom Line for This Case

In a 6-year-old female with metal foreign body ingestion, intussusception is possible but uncommon. Maintain high clinical suspicion if she develops crampy abdominal pain, vomiting (especially bilious), bloody stools, or abdominal distension. Obtain plain radiographs initially, but proceed directly to CT if complications are suspected. Most importantly, bilious vomiting in this age group is a red flag requiring urgent imaging to exclude intussusception, volvulus, or other mechanical obstruction. 1, 5