Kamraan Madhani, Stephanie Lee-Felker, Ely Felker, Harsha Desai, Krisztina Kisfalvi, Jonathan Wong, Daniel Malkhassian, James J Farrell
Context In 2011, an international symposium on Autoimmune Pancreatitis produced the International Consensus Diagnostic Criteria, which can be used to stratify patients with autoimmune pancreatitis as having type 1, type 2, or autoimmune pancreatitis – not otherwise specified. There are few studies examining the application of International Consensus Diagnostic Criteria to a cohort of North American patients with autoimmune pancreatitis. Objectives To apply International Consensus Diagnostic Criteria to a cohort of 51 patients with autoimmune pancreatitis followed at a North American medical center. To compare International Consensus Diagnostic Criteria with other guidelines with emphasis on patients who were unclassifiable using International Consensus Diagnostic Criteria. Design We applied International Consensus Diagnostic Criteria using clinical-radiological-pathological features. We reevaluated patients who were unclassifiable per ICDC with Japanese Pancreatic Society-2006, HISORt, Korean, Asian, and JPS-2011 guidelines. We statistically compared type 1, type 2, and unclassifiable patients based on demographic and clinical presentation. T-test and chi-square analysis was used for statistical analysis. Results 37 patients were categorized as definitive type 1 or type 2 autoimmune pancreatitis, 1 patient as probable type 1 autoimmune pancreatitis, and 13 were unclassifiable. Unclassifiable patients had indeterminate/atypical parenchymal imaging or none at all, and 6 patients had elevated serology. Diagnostic endoscopic retrograde cholangio-pancreatography was performed on 6 patients and 1 patient had persistent waxing and waning of clinical and radiologic features. 6 patients could be diagnosed with autoimmune pancreatitis using JPS-2006, Korean, or Asian Criteria, and 4 patients using either HISORt or JPS-2011. There was no statistically significant difference between classifiable and unclassifiable patients based on demographics or clinical presentation. Conclusions The ICDC’s dependence on histology, diagnostic endoscopic retrograde cholangio-pancreatography, and lack of acknowledgment of waxing-waning features limits applicability. Our cohort evolved during routine practice and we identify discrepancies amongst guidelines.