T cell immunity to glutamic acid decarboxylase in fulminant type 1 diabetes without significant elevation of serum amylase.

We encountered three patients with fulminant type 1 diabetes whose serum amylase levels were not elevated and evaluated their immunological characteristics. Although all three patients had no antibodies to islet antigens including glutamic acid decarboxylase (GAD), GAD-reactive T lymphocytes were detected in two patients. Combined with the findings that human leukocyte antigen (HLA) class II haplotype associated with fulminant type 1 diabetes is the same as that of autoimmune type 1 diabetes, an immune process similar to autoimmune type 1 diabetes may be involved in at least a part of fulminant type 1 diabetes.