Creation of a Case-Finding Definition for Identifying Patients With Acute Pouchitis in Administrative Claims Data

Acute pouchitis is the most common complication after a restorative proctocolectomy with ileal pouch-anal anastomosis (IPAA) for ulcerative colitis, affecting 40% of patients within the first year after surgery.¹ Although up to 80% of patients can develop pouchitis symptoms,^2,3 substantial gaps remain in our understanding of the epidemiology and burden of pouchitis. Administrative claims have been used to advance the knowledge of other areas of inflammatory bowel disease^4-6; however, a prerequisite to conducting such studies in pouchitis is a valid, reliable case-finding algorithm. Given concerns that the International Classification of Diseases (ICD) code for pouchitis may not be reliably used by clinicians (resulting in a low sensitivity), the objectives of the study were to (1) develop a series of case-finding definitions for acute pouchitis and (2) compare the performance of these case-finding definitions to that of a single ICD code for pouchitis.