IgG4 immunostaining of duodenal papillary biopsy specimens may be useful for supporting a diagnosis of autoimmune pancreatitis

Background Autoimmune pancreatitis (AIP) is now considered to be part of an immunoglobulin G4 (IgG4)-related systemic fibroinflammatory disease. Objective We evaluated whether IgG4 immunostaining of duodenal papillary biopsy specimens is useful for supporting a diagnosis of AIP. Design A prospective study. Setting A tertiary academic center. Patients/Interventions We obtained 2 forceps biopsy specimens from the major duodenal papilla (MDP) of 19...