Tag-less patency capsule for suspected small bowel stenosis: Nationwide multicenter prospective study in Japan

Study aims: The PillCam patency capsule (PPC) is an Agile tag-less patency capsule used to evaluate gastrointestinal (GI) patency. We determined the appropriate use of PPC to preclude subsequent small bowel capsule endoscopy (SBCE) retention. Methods: This prospective multicenter study consecutively enrolled patients indicated for SBCE with suspected or established small bowel stenosis. Excretion of an intact PPC or its radiologic visualization in the large bowel was considered GI patency. Primary and secondary study endpoints were SBCE retention rates in patients with confirmed patency and identification of factors associated with patency and SBCE retention, respectively. Results: Of 1096 patients enrolled in the study, patency was confirmed in 976 (89.1%). PPC excretion occurred in 579 patients. Of the remaining 517 patients, patency was confirmed using imaging modalities in 401 (77.5%). SBCE retention occurred in five (0.51%) of 963 patients who underwent SBCE: 1.0% in established Crohn’s disease (CD) patients, 0% in suspected CD, 0% in tumors, and 1.6% in patients with obscure GI bleeding, for which PPC localization had been radiographically misinterpreted. The non-confirmation of patency was associated with established CD, stenosis identified using imaging modalities, abdominal fullness, serum albumin levels <4.0 g/dL, and previous small bowel obstruction (adjusted odds ratios: 4.21, 2.60, 2.47, 2.12, and 2.00; 95% confidence intervals: 2.62–6.78, 1.62–4.17, 1.43–4.27, 1.32–3.40, and 1.15–3.47, respectively). Conclusions: The PillCam™ patency capsule helped preclude SBCE retention in most patients, but its accurate localization was essential for cases without excretion (Study registered the University Hospital Medical Information Network, #UMIN000010513).