A prospective study of the utility of abdominal radiographs after capsule endoscopy for the diagnosis of capsule retention.

Background: Capsule retention is a rare but serious complication of capsule endoscopy (CE). The utility of routine abdominal radiographs after CE for the diagnosis of capsule retention is not established.

Objective: To establish the utility of abdominal radiographs in the diagnosis of capsule retention in patients undergoing CE.

Design: Prospective cohort study.

Patients: Consecutive patients undergoing CE.

Setting: Mayo Clinic Scottsdale, Arizona, a multispecialty academic medical center.

Intervention: Abdominal radiographs were performed on days 3, 7, and 14 after CE. If the patient visualized passage of the capsule, the subsequent abdominal radiograph was cancelled.

Main Outcome And Measurements: Capsule retention, defined as the capsule endoscope seen on the day-14 abdominal radiograph.

Results: A total of 115 patients (46% men; mean age 65 years, range 20-88 years) underwent CE, which was performed for obscure GI bleeding in 86%, for suspected Crohn's disease in 5%, and for other indications in 9%. Thirty-four patients (30%) reported spontaneous passage of the capsule by day 3 and an additional 2 patients by day 7. Of the 81 reporting nonpassage by day 3, 66 (82%) underwent abdominal radiographs. Abdominal radiographs in 14 of 66 patients (21%), 3 of 12 (25%), and 2 of 3 (66%) showed a retained capsule on day 3, 7, and 14, respectively. Three patients (2.6%) were diagnosed with capsule retention. Two had serial abdominal radiographs: capsule retention was detected on the day-14 radiographs, and both underwent surgery. Histopathology revealed diaphragm disease of the small intestine in both patients. One patient who did not have serial abdominal radiographs had a small-bowel tumor as the cause of his capsule retention. In all 3 patients, the colon was not visualized on CE.

Conclusions: Capsule retention is a rare but serious complication of CE. Most patients do not visualize capsule passage. For patients who do not visualize capsule passage and, in whom the colon is not visualized on the video imaging, an abdominal radiograph on day 14 will help identify those with capsule retention.