Abstract
A 61-year-old woman had been diagnosed with diabetic ketosis at 54 years of age due to hyperglycemia (plasma glucose: 598 mg/dl, HbA1c: 14.2 %) and the presence of urinary ketones. She was admitted to a hospital, and insulin therapy was initiated based on her low endogenous insulin secretion (urinary CPR: 28 μg/day). She was admitted to the same hospital again at 56 years of age for glycemic control, at which time, she was diagnosed with type 1A diabetes due to positive GAD antibodies (337.4 U/ml). Her blood glucose level was uncontrollable as a result of exhausted endogenous insulin secretion, and she was referred to our hospital. We examined the emergence pattern of islet-associated autoantibodies using the patient's stored serum samples. Consequently, the simultaneous emergence of autoantibodies to GAD, IA-2, and ZnT8 was detected at the onset of type 1 diabetes. Although GAD antibodies were persistently positive, autoantibodies to IA-2 and ZnT8 became negative within three years after disease onset. The emergence of islet-associated autoantibodies generally occurs before the clinical development of type 1 diabetes. We herein demonstrated a rare case of type 1 diabetes in which islet-associated autoantibodies developed simultaneously, not sequentially.
