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Updated: Jun 2, 2026

Handheld Metal Detector Screening for Metallic Foreign Body Ingestion in Children
Published on: September 11, 2018
Initial location determines spontaneous passage of foreign bodies from the gastrointestinal tract in children
Ji Hyuk Lee1, Jong Seung Lee, Mi Jin Kim
1From the Department of Pediatrics, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, South Korea.
Insights
Most ingested foreign bodies (FBs) in children pass spontaneously, especially when located below the esophagus. Initial location and size are key predictors of spontaneous passage (SP), with most FBs passing within 5 days.
Area of Science:
- Pediatric Gastroenterology
- Gastrointestinal Endoscopy
- Medical Device Safety
Background:
- Foreign body ingestion is a common pediatric emergency.
- Understanding the natural course of ingested foreign bodies (FBs) is crucial for management decisions.
Purpose of the Study:
- To investigate the spontaneous passage (SP) rates and outcomes of ingested foreign bodies in children.
- To identify factors influencing the spontaneous passage of FBs.
Main Methods:
- Retrospective review of 249 pediatric patients with ingested FBs.
- Telephone questionnaires used to track spontaneous passage of FBs.
- Analysis of factors including age, FB type, size, and initial location.
Main Results:
- Spontaneous passage occurred in 58.2% of cases; endoscopic removal in 40.2%.
- Initial location significantly impacted SP rates: esophagus (12.2%) vs. colon (96.4%).
- FB location and size were independent predictors of SP (p<0.0001).
Conclusions:
- Most ingested FBs in children pass spontaneously without complications.
- Initial FB location is the primary determinant of spontaneous passage.
- Even sharp or large FBs can pass spontaneously if located distal to the esophagus.
Objective:
The purpose of this study was to follow the natural course of spontaneous passage (SP) of ingested foreign bodies (FBs) in children.
Methods:
The medical records of 249 patients who ingested FBs were reviewed. In addition, they were studied by telephone questionnaires to follow up spontaneously passed FB. The factors associated with SP such as age, the type, size, and initial location of the FBs were analyzed.
Results:
Foreign bodies were spontaneously passed in 145 patients (58.2%), endoscopic removal was performed in 100 patients (40.2%), and operative removal was performed in 4 patients (1.6%). Most SP FBs were passed within 5 days. The SP rates (SPRs) according to the initial location were the following: 12.2% for the esophagus (P<0.0001), 71.4% for the stomach, 85.7% for the small bowel, and 96.4% for the colon. There was no significant difference in the SPR according to age. When coins and disk batteries that required early endoscopic removal were excluded, the SPR was 63.4% for FBs less than 10 mm, 80.4% for FBs 10 to 20 mm, 72.8% for FBs 20 to 30 mm, and 50.0% for FBs more than 30 mm (P=0.091). The initial location of the FB (odds ratio, 33.7; 95% confidence interval, 14.4-79.0) and the size of the FB (odds ratio, 3.5; 95% confidence interval, 1.0-11.6) were independent predictors of SP by multivariate analysis.
Conclusions:
Most FBs in the gastrointestinal tract are spontaneously passed without complication, and the initial location of FBs was found to be the main determining factor for SPR. Ingested FBs, in children, even sharp or relatively large FBs, can be spontaneously passed when they are located below the esophagus.
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