Specifically, Ewald and Bretzel [14] proposed the following diagnostic criteria: (all of the following must be met) - A diagnosis of diabetes mellitus - Evidence of exocrine pancreatic insufficiency (fecal elastase 1 [FE1] < 200 μg / g or abnormal direct function testing) - Abnormal pancreatic imaging (endoscopic ultrasound, magnetic resonance imaging, and computed tomography) - Absence of T1DM associated autoimmune markers (antibodies against glutamine acid decarboxylase, islet cell antigen, or insulin) [14].