A 29 year old lady presented to an outside hospital with 1 years history of episodes of confusion in the mornings. The patients partner had noticed that 23 times a week she awoke with episodes of confusion, minimal communication, stereotyped lip smacking and winking lasting up to 20 min. She had one nocturnal tonic-clonic seizure abroad, requiring A+E attendance. She was then seen by a neurologist, had a normal sleep deprived EEG and was diagnosed with focal epilepsy and started on lamotrigine. She subsequently had two further episodes of nocturnal/early morning tonic-clonic seizure whilst in the UK, on anti-epileptic medications. A CBG of 1.2 mmol/l was recorded by the ambulance service after one of these seizures. After this, she would wake herself in the night to consume a banana and a can of Coca Cola, which prevented further seizures. She had experienced some weight gain. Family history was remarkable for type 2 Diabtes Mellitus in a grandmother and thyrotoxicosis in her mother. Physical examination was unremarkable. A 72-hour fast was planned, however, the patient had an episode of hypoglycaemia prior to the test starting, with a lab glucose of 1.6 mmol/l, insulin was inappropriately detectable at 9.8 mu/l with a c-peptide of 765.6 pmol/l. A urinary sulphonylurea screen was negative. Results were compatible with insulinoma. Other blood parameters were normal. MRI pancreas showed a 1 cm soft tissue lesion arising from the pancreatic tail, this lesion was avid on a 68Gallium-Dotate PET-CT. No evidence of metastatic disease was seen. The patient was referred for surgery. Management of the hypoglycaemia was challenging. The patient had a disappointing response to escalating doses of diazoxide, still requiring a midnight snack to prevent hypoglycaemia. Octreotide was unhelpful and resulted in nausea and reduced intake, leading to re-admission with further hypoglycaemic episodes. Symptoms persisted despite the addition of anti-emetic medication and the octreotide was stopped and prednisolone commenced and the dose gradually increased to 10 mg morning, 5 mg evening until the hypoglycaemic episodes were abolished. Diazoxide induced oedema was managed with Bendrofluazide. The patient underwent a distal pancreatectomy and splenectomy. Histology showed a completely excised 13mm NET, Ki67 <5% with no evidence of vascular invasion. Immunohistochemistry showed expression of chromogranin and synaptophysin with weak staining for insulin. Post-operatively, there have been no further hypoglycaemic episodes.
16 - 18 Apr 2018
Society for Endocrinology