Case Report: Autoimmune Pancreatitis Mimicking Cancer of the Head of Pancreas

Autoimmune pancreatitis (AIP) is a rare disorder that may be present as common bile duct stricture. The patient was a seventy-year-old man with presentations as recurrent abdominal pain and jaundice, elevated Billirobin (Bil) and elevated Alkaline Phosphatase (ALKP) in association with the presence of hetrogenesity of the pancreatic head and dilated intra and extra hepatic bile ducts in CT. Such clinical features confirmed the diagnosis of cancer the head of pancreas, therefore, was taken common bile duct stent for him. The patient came back with continuation recurrent abdominal pain and normal (Bil, ALKP and tumor markers) but remarkable elevated IgG4 and anti nuclear antibody. The patient was biopsied of hetrogenesity of the Pancreatic head by Endoscopic Ultra Sonographic (EUS)-guided. In the pathology of the pancreatic head, was observed fibrosis with Lymphoplasmacitic infiltration without the presences of malignancy. Finally, the patient was treated with the diagnosis of autoimmune Pancreatitis and was gone out bile duct stent.