Autoimmune pancreatitis with spontaneous remission on ¹⁸F-fluorodeoxyglucose positron emission tomography/computed tomography

Abstract

A 79-year-old man with elevated blood glucose was started on insulin therapy. IgG4 was as high as 1,830 mg/dL, and ¹⁸F-fluorodeoxyglucose-positron emission tomography/computed tomography (FDG-PET/CT) confirmed diffuse pancreatic enlargement and accumulation of FDG. Based on the above, autoimmune pancreatitis (AIP) was diagnosed, but steroid treatment was not performed. IgG4 later declined, and FDG accumulation in the pancreas disappeared on FDG-PET/CT at the age of 83 years. AIP was thought to have gradually remitted spontaneously over time. FDG-PET/CT is useful for evaluating AIP activity.