This patient was a 52-year-old man diagnosed with type 2 diabetes mellitus at the local hospital according to a fasting glucose test that showed a concentration of 16 mmol/L. His postprandial glucose concentration was 27 mmol/L. However, the patient was asymptomatic. He was then treated with a 50/50 Mixture Recombinant Human Insulin Injection (Gansulin 50R) of 12–16 units twice a day, and the dose had been adjusted to 6–10 units 2 months previously. During this period, his glucose was well controlled. One month previously, he developed dizziness and was flustered again. He also started sweating excessively, and at that time, his fasting plasma glucose concentration was 2.8 mmol/L. One week previously, the treatment was changed to acarbose 0.1 mg three times a day because of repeated occurrence of hypoglycemic symptoms. His insulin concentrations were 1294.01/1303.77/1456.7/2057.11/2032.41 pmol/L at 0/30/60/120/180 min and C-peptide concentrations were 1.30/1.80/2.21/2.87/2.55 nmol/L at 0/30/60/120/180 min during the OGTT, respectively. The anti-insulin antibody test was positive. He was prescribed metformin (0.5 g twice a day), acarbose (0.05 g three times a day), aspart (6–5-5 units three times a day), and methylprednisolone (4 mg three times a day) for glucose control. After these changes, hypoglycemia syndrome did not recur (Table ).
This patient was a 79-year-old man who had a 10-year history of hyperglycemia in addition to fluctuating glucose concentrations for more than 1 year. This was accompanied by diabetic nephropathy as well as a history of gout for more than 30 years. His glucose concentrations were initially well controlled with metformin after diagnosis of type 2 diabetes mellitus. A subcutaneous insulin pump (lispro) was recently added to his treatment regimen for renal insufficiency, and metformin was gradually changed to Humulin R (6–4-4 units, three times a day) combined with glargine 12 units a day. Thereafter, he had recurrent midnight hypoglycemia and daytime hyperglycemia, with blood glucose concentrations up to 20 mmol/L. Therefore, he was treated with acarbose (50 mg three times a day) instead of insulin injections. At this time, his C-peptide values were 5.45/6.94/6.94/7.89/7.17 nmol/L at 0/0.5/1/2/3 h, respectively (normal range: 0.27–1.28 nmol/L). His insulin concentrations were > 1000.00/> 1000.00 pmol/L at 0/2 h, respectively (normal range: 13–161 pmol/L), during an oral glucose tolerance test (OGTT), his HbA1c concentration was 10.2%, and an anti-insulin antibody test was positive (reference level: < 0.4). His glucose concentrations still fluctuated between 11 mmol/L and 22 mmol/L in the daytime, while hypoglycemia occurred at night. Subsequently, acarbose (100–100-50 mg three times a day) and sitagliptin (50 mg per day) were prescribed for symptom management, and his glucose concentrations returned to the normal range. Laboratory findings at a 1-year follow-up showed an HbA1c concentration of 7.0%, insulin concentrations of 138.53/733.40 pmol/L at 0/2 h, and C-peptide concentrations of 1.35/2.21 nmol/L at 0/2 h, respectively.