Capsule Endoscopy: Is There Value of a Negative Study?

Abstract

Background: Capsule endoscopy (CE) is an ambulatory, sensitive, non-invasive technique primarily used for evaluation of the small intestine. In the setting of obscure gastrointestinal bleeding (OGIB) it has a high diagnostic yield. Our group previously demonstrated that a negative CE likely has a benefit in reducing specific aspects of resource utilization. Objective: This study extended patient follow-up to determine if the initial benefit of a negative CE on aspects of resource utilization continues. Methods: Negative CE studies completed at a single academic centre were reviewed. Of 310 capsule studies (12/01 to 11/04), 267 were for OGIB and 105 of these were negative. The review was performed to collect data on investigations (endoscopic and non-endoscopic), transfusions and management pre and post CE. Most of the information was available from the prospectively collected CE database; however, in cases where data was absent, patients and/or referring physicians were contacted. We had 12 months of assessment prior to and post capsule study in 80%. Statistical analysis was carried out using McNemar's and Wilcoxon Signed Rank Tests. Results: Data is available on 88 of the 105 negative CE studies. The number of patients undergoing ≥3 upper endoscopies before negative CE were proportionally greater than those requiring ≥3 after CE (36 vs 2%, p < .001). The number of colonoscopies decreased post CE (median: 2 vs 0, p < .001). The number of small bowel barium studies was significantly less after CE (58 vs 3%, p < .001). Nuclear scans and angiograms were less frequently required post CE (30 vs 8%, p < .001). Transfusion requirements also decreased post CE (≥5 units PRBCs: 31 vs 17%, p < .001). Surgery after CE was performed in 14 patients (16%) which were directed by the negative capsule study. In addition, 3 other abnormalities (previously noted endoscopically) were treated with therapeutic endoscopic intervention. Conclusion: A negative CE is associated with a decreased requirement for further small bowel investigations even with follow-up extending up to one year. This demonstrates a clear benefit and potential for cost savings. In addition, blood transfusion requirements also decrease, potentially indicating a group of patients with ‘milder’ disease.