Endocrine Abstracts

A 36 year old gentleman with a BMI of 22 was seen in diabetes clinic. He had a 1 year history of type 2 diabetes (and no family history of diabetes). He was on insulin but had later been started on metformin and had been able to reduce his insulin dose. He was advised to continue reducing his insulin dose and the consultant decided that due to the patient’s morphology he would request an IGF-1 level. At his next follow up the patent had vastly reduced his insulin doses and his glycaemic control was very good. His IGF-1 result had come back significantly elevated at 175 nmol/l (reference range 8.3–29.2). On further questioning the patient had not noticed any particular change in his facial features or in the size of his hands or feet over the years. He had no problems with dentition but did tend to get quite sweaty. He had no history of hypertension. He felt generally very well and had no headache. On examination he had morphological features of acromegaly. His hands were large, especially for his height. He had slight bossing of the forehead and moderate macrognathia. Visual fields were normal as was cranial nerve examination. His blood pressure was normal. The patient had the significance of the elevated IGF-1 level explained to him. He was booked in for a growth hormone suppresion test and an MRI of his pituitary was requested. He was referred to the joint pituitary clinic. In due course he had the growth hormone suppression test and his growth hormone production failed to suppress having had a glucose drink (GH 14.27 ng/ml at 0 minutes, 10.69 ng/ml at 60 minutes and 12.96 ng/ml at 120 minutes). The rest of his biochemical pituitary profile was normal. The MRI showed a 8 mm by 9 mm by 10 mm poorly enhancing lesion on his pituitary gland. There was no chiasmal involvement. The findings and options were discussed in the joint pituitary clinic and the patient agreed to have a trans-sphenoidal adenectomy. The surgery was performed 6 months later and the adenoma was resected endoscopically (endonasally). Aside from elevated blood glucose levels in the aftermath of the surgery, his recovery was unremarkable. Histology reported a pituitary adenoma with production of growth hormone and prolactin. Recent IGF-1 at 3 months was 63.8 nmmol/l and the patient is due to be seen in clinic very soon.