Clinical Evaluation of 4 Patients with Fulminant Type 1 Diabetes Mellitus without Marked Elevation of Serum Amylase at Onset

Abstract

We report 4 patients with abrupt-onset type 1 diabetes mellitus characterized by the absence of diabetesrelated autoantibodies similar to the subtype reported by Imagawa et al.Hemoglobin Aic ranged from 5.0% to 7.9%. Urinary excretion of C-peptide was lower than 5 μg/day and the serum concentration of C-peptide after glucagon injection was lower than 0.3 ng/ml in all 4 patients, 3 of whom tested negative for glutamic acid decarboxylase (GAD) antibodies.GAD antibody was slightly elevated in the other patient, but this was not considered significant.Islet-cell antibodies were not detected in any of the 3 patients tested. These patients did not have significantly elevated serum amylase typically seen in fulminant type 1 diabetes mellitus. Two of our patients had signs of upper respiratory viral infection shortly before diabetes onset. All 4 patients had HLA-A 24 and DR 4 and/or DR 9. Our findings suggest that fulminant type 1 diabetes mellitus is not necessarily accompanied by elevated serum pancreatic enzyme and that HLA-A 24 may play a role in abrupt-onset type 1 diabetes mellitus characterized by the absence of diabetes-related autoantibodies.