Endocrine Abstracts

Introduction: Insulin resistance occurs in 80% of patients with acromegaly. This report illustrates the case of a female patient with unsatisfactory control of type 2 diabetes and a beneficial effect on glycaemic control after the somatotropic pituitary adenoma surgery.

Case report: A 76-year-old female patient with diabetes diagnosed more than twenty years ago was treated with oral hypoglycaemic agents for a long time. In the past ten years she has been taking insulin and has had extremely poor glycaemic control for a long time. She presented with an average daily level of blood glucose 11.2 mmol/l (measured by the device for self-monitoring of blood glucose before and two hours after the main meals) and HbA_1c 9%, while taking 62 units of insulin as a total daily dose. On that occasion the body mass index (BMI) was 23.8 kg/m², since the patient weighed 61 kg and was 1.6 m tall.

The patient had slightly visible signs of acromegaly. Therefore she underwent IGF-1 tests which showed high levels on two occasions, 380 and 369 μg/l (standard levels being 59–177 μg/l for the patient’s age). An MRI scans showed sellar and infra-sellar macroadenoma and the patient underwent a transphenoidal surgery. Two months postoperatively the IGF-1 test showed 94.5 μg/l, the average daily level of blood glucose was 7.6 mmol/l, HbA_1c 7.2%, and the daily dose of insulin was 16 units.

Conclusion: This case confirms the significance of an analytical approach to each patient with unsatisfactory glycemic control. The significant reduction of the daily dose of insulin after the somatotropic pituitary adenoma surgery as well as attaining satisfactory glycemic control proves that growth hormone significantly affects insulin resistance.