Endocrine Abstracts

Non-Islet Cell Tumour Hypoglycaemia (NICTH) is a rare paraneoplastic phenomenon caused by aberrant production of pro-IGF-II from tumours, usually mesenchymal or epithelial in origin. Previous case studies report significant reduction in hypoglycaemia with tumour resection, while medical therapy with glucocorticoids and sometimes growth hormone has reduced the frequency of events in some cases. A 63 year old non-diabetic lady presented with a collapse and episodes of fatigue, disorientation and confusion. Her medical history included ulcerative colitis treated with colectomy, during which peritoneal nodules were noted and biopsy showed a fibrous tumour of uncertain malignant potential. On this occasion, transient ischaemic attack and possible early dementia were thought to have caused her presentation, but a thorough history by her GP prompted further investigation, which revealed a fasting hypoglycaemia of 1.6 mmol/l. Admission for a 72-hour fast was arranged and blood samples taken during a hypoglycaemic event revealed low insulin <10 pmol/l and C-peptide <94 pmol/l. Further analysis found a raised IGF-II:IGF-I ratio 26.3 (<10), consistent with a diagnosis of Non-Islet Cell Tumour Hypoglycaemia (NICTH). Imaging revealed a large pelvic mass, confirmed on biopsy as solitary fibrous tumour. A debulking procedure was planned. Meanwhile, she was taught to self-monitor and manage episodes of hypoglycaemia. These became less frequent with the addition of prednisolone 20 mg, but continued to occur even after surgery. Previous cases reports have shown little benefit from diazoxide or octreotide. Over the course of 3 years she developed progressive cognitive impairment, thought to be due to recurrent hypoglycaemic state. During her final admission she was unable to continue with oral intake and glucose was maintained with IV dextrose and IV hydrocortisone. A palliative approach was adopted as no further treatment options were available. Non-Islet Cell Tumour Hypoglycaemia is a rare paraneoplastic phenomenon caused by aberrant production of pro-IGF-II from tumours, usually mesenchymal or epithelial in origin. Previous case studies report significant reduction in hypoglycaemia with tumour resection, while medical therapy with glucocorticoids and sometimes growth hormone has reduced the frequency of events in some cases. This case demonstrates that it can be difficult to diagnose recurrent hypoglycaemia and NICTH as the vague symptoms can be misinterpreted as more common illnesses. Therefore it may be worth considering hypoglycaemia when investigating patients presenting with symptoms such as confusion or collapse.