Magnetic Foreign Body Ingestions Leading to Duodenocolonic Fistula

INTRODUCTION

Foreign body ingestion is a common presentation to general pediatricians and pediatric gastroenterologists. Although specific foreign bodies such as sharp objects or batteries are well-known to cause certain complications, the complications associated with magnetic foreign body ingestions are not as well-known (¹). Most of the published cases regarding magnetic foreign body ingestions are reported in Asian literature, likely because magnets are commonly sold in drugstores in Asian countries as remedies for ailments such as muscle stiffness, and their size and shape make them easy to swallow (^2,3). In this case, we report a complication of multiple magnet ingestions.

CASE REPORT

A 7-year-old male with a history of developmental delay and agenesis of the corpus callosum presented to an outside hospital with a 3 day history of fever, dysuria, and foul-smelling urine. Physical examination was significant only for general irritability and suprapubic tenderness. Urinalysis was consistent with a urinary tract infection, and the patient was admitted for pyelonephritis. The patient had persistent irritability despite therapy with intravenous antibiotics, and constipation was suspected. After an enema yielded no results, an abdominal radiograph was obtained. The abdominal film revealed the presence of 10 foreign bodies arranged in tandem (Fig. 1). The patient is ambulatory and has a history of pica. The patient's mother recognized the shapes of the foreign bodies as magnetic construction toys (Supermag by Plastwood) that had been purchased 4 months earlier. However, because the ingestion was unwitnessed and the patient is nonverbal, the timing of the ingestion could not be ascertained. The patient was transferred to our hospital for retrieval of the foreign bodies.

Fig. 1

An upper endoscopy was performed under general anesthesia to retrieve the magnetic foreign bodies. The foreign bodies were visualized from the pylorus to the second portion of the duodenum, and 6 of the 10 pieces were removed using only combination forceps (large rat-tooth forceps with alligator jaws, Olympus FG-42L-1, Olympus America Inc., Lake Success, NY). However, only one remaining piece could be seen in the second portion of the duodenum. An intraoperative radiograph showed four pieces still connected in tandem. The one piece that could be seen appeared to be embedded in the duodenal wall with surrounding mucosal erosions. A surgery consult was obtained for suspected bowel perforation despite the lack of free air on the radiograph. Before laparotomy, the endoscope was reintroduced. The foreign body was no longer present, and what was thought to be a perforation in the duodenal wall was seen. At laparotomy, the four foreign body pieces were palpated inside the lumen of the ascending colon. These were removed through a small colostomy. The duodenum was mobilized, and a duodenocolonic fistula was discovered (Fig. 2). The fistula was divided, and the duodenum and colon were each repaired in two layers using standard surgical techniques. The 10 magnets maintained a strong attraction to each other after being removed from the patient.

Fig. 2

DISCUSSION

We describe a patient who developed a fistula after the ingestion of magnetic foreign bodies. We speculate that the patient ingested the foreign bodies at different times. The magnets that had been ingested the earliest had probably progressed to the colon when their progress was halted by their attraction to the magnets ingested later, which were in the duodenum. The pressure exerted on the respective walls of the bowel from the attraction of the magnets likely led to fistula formation. Given the maturity of the fistula, it is likely that the foreign bodies had been present for several weeks.

Magnetic foreign body ingestions leading to fistula formation, obstruction, and perforation have been described in the literature. There are several cases reported from Japan, where small magnets are commonly sold for the treatment of muscle stiffness by placing them over the affected areas and securing them with adhesive plaster. These types of therapeutic magnets were involved in a case, described by Honzumi et al. (²), in which a 3-year-old girl ingested 11 small tablet-like magnets, resulting in the formation of a jejunoileal fistula. They also cite two Japanese articles by Takahashi et al. and Ohkubo et al. who reported cases of magnet ingestion that caused strangulated intestinal obstruction with an ileoileal fistula and four intestinal perforations, respectively. Kubota et al. (⁴) described an unwitnessed ingestion of multiple magnets in a 17-month-old female, which presented as intestinal obstruction. In that case, the magnets, which are commercially available in Japan for the treatment of shoulder stiffness, formed a jejunoileal fistula that strangulated an adjacent loop of small intestine. Two Korean reports describe complications associated with magnetic foreign body ingestions. Lee et al. (⁵) reported the formation of a jejunojejunal fistula in a 2-year-old girl and a gastrojejunal fistula in a 3-year-old girl, both resulting from the same kind of 2 × 1.5 cm magnetic bead that is a component of bracelets or necklaces worn for naturalistic or holistic healing power. Chung et al. (³) also reported two separate cases of ileoileal fistulas formed by magnetic objects. One case involved a 10-month-old boy who ingested two magnetic beads from a necklace used for the treatment of muscle stiffness, and the other case involved a 22-month-old boy who ingested seven small tablet-like magnets. Ohno et al. (⁶) described formation of a gastroduodenal fistula after ingestion of magnetic construction toys by a 7-year-old autistic girl. In England, Cauchi and Shawis (⁷) described a case of intestinal perforation in a 9-year-old girl after the intentional ingestion of 12 small magnets. The patient reportedly ingested the magnets intentionally to allow for the application of jewelry, to mimic body piercing. Interestingly, the technique of magnetic compression anastomosis, in which a nonsurgical, sutureless enteric anastomosis is created using two samarium-cobalt rare-earth magnets in conjunction with interventional radiologic techniques, arose from the case of fistula formation from magnet ingestion described by Honzumi (^2,8).

Although it appears that reports of multiple magnet ingestion are rare, it is also clear that serious complications can arise from such ingestions. A patient who ingests a single magnet that is small enough to pass through the gastrointestinal (GI) tract without complication can likely be observed without intervention. However, the literature and our experience show that the magnetic attraction of foreign bodies in different locations of the GI tract can lead to complications such as intestinal perforation, fistula formation, and intestinal obstruction. It is also possible that an intraperitoneal hemorrhage could occur if mesenteric vessels present between attracted bowel walls. Given our case and review of the literature, we would recommend that a patient who ingests multiple magnets, or multiple objects that may attract while in the GI tract, be referred to a gastroenterologist immediately for endoscopic removal. If the magnets have passed out of the reach of an endoscope, serial radiographs should be performed. If these studies show that the magnets are stationary, then operative intervention, in the form of a laparotomy or laparoscopic exploration, should be performed to retrieve the magnets and prevent further complications.