An obese patient with slowly progressive type 1 diabetes diagnosed by ketoacidosis.

The patient was a 69-year-old woman with a family history of type 2 diabetes. Her body mass index was 31.5. She was diagnosed as type 2 diabetes 32 years previously, and treated with insulin for 8 years. She had no episode of weight loss. She was hospitalized with diabetic ketoacidosis for the first time. Her GAD antibodies were not detected. However, ICA antibodies and insulin antibodies were positively detected. She was diagnosed with type 1 diabetes. Interestingly, her diabetes state was controlled to the same level after recovery from ketoacidosis.