Endocrine Abstracts

We describe the case of a 76 year old woman who presented to her GP with a two month history of abdominal pain, tiredness and nocturnal sweating episodes. Her past medical history included Hypertension (on Amlodipine, Bisoprolol) and Hypothyroidism (on levothyroxine). Abdominal USS and CT scan revealed a left adnexal mass measuring 15 cm. Ca-125 and CEA were normal. During admission under the Gynae-oncologists for a laparotomy, she suffered recurrent severe symptomatic hypoglycaemia (episodes of agitation and sweatiness) with venous plasma glucose readings down to 1.2 mmol/l. She was resuscitated with intravenous glucose infusions. Plasma Insulin was <1.0 mu/l, TSH 13.14 mU/l, fT4 16.6 pmol/l, normal Short Synacthen Test, FBC, U&Es, LFTs and CRP. She underwent TAH and BSO. At operation she was found to have a large uterus with multiple fibroids. Histology showed cellular leiomyoma and immunostaining was negative for Insulin, Chromogranin and Synaptophysin. These hypoglycaemic episodes completely resolved following hysterectomy.

Nonislet cell tumour hypoglycaemia (NICTH) is observed in some mesenchymal, epithelial, haematological and lymphoid tumours. To the best of our knowledge, there is only one case report of a solitary fibrous tumour of uterus producing high molecular weight IGF-II and hypoglycaemia. Most of the NICTH cases are explained by increased glucose utilization due to secretion of incompletely processed IGF-II by the tumour. This abnormally processed IGF-II interacts more readily with Insulin receptors in target tissues and results in increased glucose uptake by peripheral tissues and inhibition of glucose production by the liver. High levels of plasma IGF-II and low plasma levels of IGF-I, insulin, pro-insulin, C-peptide, Growth Hormone levels are often found in NICTH patients. Management strategies include correction of acute hypoglycaemia and treatment directed at the underlying tumour. Frequent feeding and administration of GH, Glucagon and glucocorticoids can also be effective.