S763 Twenty Percent of Patients With Inflammatory Conditions of the Pouch Demonstrate a More Refractory Disease State Within Twelve Months of Enrollment in a Multicenter Prospective Registry

Abstract

Introduction: Up to 80% of patients will develop pouchitis after proctocolectomy with ileal pouch-anal anastomosis (IPAA) for ulcerative colitis, and approximately 10% will develop Crohn’s disease (CD) of the pouch. We designed a geographically diverse, eight-center, prospective registry to study the disease course among patients with one of four inflammatory conditions of the pouch. The aim of this study was to evaluate patterns of changes in diagnosis during the first 12 months after enrollment. Methods: We enrolled patients with a confirmed diagnosis of acute pouchitis, chronic antibiotic dependent pouchitis (CADP), chronic antibiotic refractory pouchitis (CARP), or CD of the pouch. Diagnoses were based on standardized criteria and we obtained detailed clinical and demographic data at the time of enrollment. Patients completed follow-up assessments at 3, 6, and 12 months after enrollment, with treating physicians confirming their respective diagnoses at each time point. Associations between clinical and demographic data at baseline and a switch in diagnosis to a more refractory disease state were analyzed using chi-square testing. Results: We enrolled 318 patients (10% acute pouchitis, 27% CADP, 12% CARP, and 51% CD of the pouch). During the first 12 months after enrollment, 31 of the 157 patients (20%) without CD of the pouch at enrollment switched diagnosis to a more refractory disease state, with 20 of 31 (65%) patients ultimately being diagnosed with CD of the pouch. Among 7 patients with acute pouchitis who switched diagnoses, 5 were diagnosed with CADP, 1 with CARP, and 1 with CD of the pouch. Among 19 patients with CADP who switched diagnoses, 4 were diagnosed with CARP and 15 were diagnosed with CD of the pouch. Four patients with CARP had a change in diagnosis to CD of the pouch during the study period. Patients who experienced a change in diagnosis were significantly more likely to be current smokers when compared to patients with no change in diagnosis during the study period (23% vs. 5%, p=0.001, Table). Conclusion: In a prospective registry of 318 patients from eight centers in the United States, 20% of patients without CD of the pouch at enrollment experienced a change in diagnosis to a more refractory inflammatory condition of the pouch during the first 12 months after enrollment. Patients who were current smokers were more likely to change diagnoses, and may represent a high risk group for earlier intervention and targeted smoking cessation efforts after IPAA. Table 1. - Comparison of Baseline Demographics and Clinical Characteristics of Patients with an Inflammatory Condition of the Pouch and a Change in Diagnosis to those with No Change in Diagnosis Change in Diagnosis within 12 Months of Enrollment n=31 No Change in Diagnosis within 12 Months of Enrollment n=287 p-value Median IQR Median IQR Current Age 50 44-59 52 38-62 0.873 n % n % Female Sex 12 39 129 45 0.636 Race >0.999 White 29 94 263 92 Black 1 3 16 6 Other 1 3 8 3 Hispanic ethnicity 3 10 7 2 0.063 BMI 0.271 Normal 17 55 114 40 Overweight 7 23 99 34 Obese 7 23 71 25 Disease extent prior to surgery 0.447 Proctitis 2 6 19 7 Left-sided colitis 5 16 22 8 Extensive colitis 19 31 151 61 Unknown 4 13 52 18 Indication for surgery >0.999 Medically-refractory colitis 29 94 256 89 Dysplasia/colorectal cancer 1 3 13 5 Medically refractory + dysplasia/colorectal cancer 0 0 8 3 Other 1 3 9 3 Number of stages in surgery 0.590 1 2 6 35 12 2 10 32 114 40 Modified 2 3 10 19 7 3 15 48 103 36 IPAA surgery performed at current medical center 20 65 181 63 >0.999 Primary Sclerosing Cholangitis 2 6 23 8 >0.999 Clostridiodes difficile infection prior to IPAA 4 13 42 15 >0.999 Smoker at the time of colectomy 2 6 15 5 0.678 Current smoker 7 23 13 5 0.001 NSAIDs in the prior two weeks 12 39 104 36 0.846