Copyright: ©Author(s) 2026. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution-NonCommercial (CC BY-NC 4.0) license. No commercial re-use. See permissions. Published by Baishideng Publishing Group Inc.
World J Gastrointest Pharmacol Ther. Jun 5, 2026; 17(2): 113874
Published online Jun 5, 2026. doi: 10.4292/wjgpt.v17.i2.113874
Published online Jun 5, 2026. doi: 10.4292/wjgpt.v17.i2.113874
Right biopsy protocol for microscopic colitis: Reduced workload and carbon footprint while maintaining diagnostic accuracy
Edric Leung, Yasir Alshareefy, Conor Costigan, Sandeep Sihag, Sarah O’Donnell, Niall Breslin, Anthony O’Connor, Barbara Ryan, Fintan O’Hara, Deirdre McNamara, Department of Gastro
Edric Leung, Conor Costigan, Sandeep Sihag, Deirdre McNamara, Trinity Academic Gas
Sarah Delaney, Department of Cellular Pathology, Tallaght University Hospital, Dublin D24 NR0A, Ireland
Abdul Zaheer, Ion Cretu, Department of Gastroenterology, Naas General Hospital, Kildare W91 AE76, Ireland
Author contributions: Leung E and Alshareefy Y acquired and curated the data; Leung E and McNamara D conceived and designed the study, analyzed and interpreted the data, and drafted and critically revised the manuscript; Alshareefy Y, Costigan C, Sihag S, Delaney S, O’Donnell S, Breslin N, O’Connor A, Ryan B, Zaheer A, Cretu I, and O’Hara F contributed to the study design and critical review of the manuscript. All authors approved the final manuscript.
Institutional review board statement: This study was approved by the Clinical Audit Manager of Tallaght University Hospital. Formal ethics committee approval was not required owing to the retrospective study design.
Informed consent statement: Patients were not required to give informed consent for the study, as the analysis used anonymized clinical data obtained after each patient had provided written consent for treatment.
Conflict-of-interest statement: All the authors report no relevant conflicts of interest for this article.
STROBE statement: The authors have read the STROBE Statement-checklist of items, and the manuscript was prepared and revised according to the STROBE Statement-checklist of items.
Data sharing statement: sharing statement: The data underlying this article are available from the corresponding author upon reasonable request.
Corresponding author: Edric Leung, Department of Gastroenterology, Tallaght University Hospital, Tallaght, Dublin D24 NR0A, Ireland. edric.leung@tuh.ie
Received: September 9, 2025
Revised: November 13, 2025
Accepted: January 27, 2026
Published online: June 5, 2026
Processing time: 263 Days and 18.5 Hours
Revised: November 13, 2025
Accepted: January 27, 2026
Published online: June 5, 2026
Processing time: 263 Days and 18.5 Hours
Core Tip
Core Tip: Current guidelines recommend biopsies from both the right and left colon for diagnosing microscopic colitis; however, the optimal strategy remains uncertain. In this retrospective study of 228 index colonoscopies in patients with microscopic colitis, right colon biopsies were diagnostic in all cases, while left colon biopsies had a significantly lower yield and provided no additional diagnostic value. These findings suggest that a simplified protocol of two right colon biopsies in a single container could preserve diagnostic accuracy while reducing workload, cost, and carbon footprint, consistent with green endoscopy principles.