Pseudotumoral Auto-Immun Pancreatitis with Multiple Pancreatic Pseudo-Cysts: A Diagnosis Pitfall

Introduction: The autoimmune pancreatitis (AIP) is a chronic inflammatory disease secondary to autoimmune disorders. Its s considered as a manifestation of IgG4 related disease. Case Report: We report an exceptional case of AIP of a patient who presented with nonspecific symptoms leading to an MRI-diagnosis of a pancreatic tale tumor with strong presumption of cystadenocarcinoma rather than adenocarcinoma. Histopathological study revealed a tense lymphoplasmacytic infiltrate associated with storiform fibrosis and collagenization. Furthermore; many pseudocysts were associated lesions immunohistochemical tests revealed a diffuse staining of plasma cells by IgG and IgG4 antibodies. The diagnosis of an AIP with multiple pseudocysts mimicking a pancreatic tale tumor was made. Conclusion: These, all criterions considered together made our case, a rare entity that may be a challenging diagnosis leading sometimes, as the current case, to a massive surgery