Endocrine Abstracts

51 year male ex-professional hockey player, now works as a coach 2 years ago had knee injury and was less active. He gained 3 stone weight over 2 years and feels that he needs to eat more. Started ketogenic diet (PronoCal) for trying to lose weight. The day after starting this diet spent one hour in gym and whilst playing tennis developed double vision. Then he ate lunch at 12 pm mostly protein and vegetables. Che had conference call at work between 4-5 pm and his writing was illegible during that time. Then he had protein bar and went to sleep. Found by wife at 20:30 lying in bed, before becoming acutely confused at 01:00 in the morning. At that time patient was half off bed, bizarre behaviour, confused and slurred speech. Ambulance was called his blood glucose was found to be 2.2 mol/l and confusion improved when given glucogel. He was then admitted to hospital, denies any use of medication or supplement. He also mentions that his wife has noticed that he sweats a lot and will occasionally be tachypnoeic at night. On further questioning remembers having few episodes of feeling lightheaded last year, like he needs sugar. This usually occur in evening after meals and hasn’t noticed similar symptoms in the mornings, but does feel like needs an early lunch sometimes. Brain imaging was nil significant. After prolonged fasting as inpatient while blood glucose was 2.1 mmol/l serum insulin 267 pmol/l and c-peptide high at 1015 pmol/l with negative sulphonylurea screen. CT pancreas showed 18 mm lesion arising from tail of pancreas. Endoscopic ultrasound showed 2.4 × 9.1 hypoechoic vascular mass inferior to pancreatic tail. NM Ga68 DOTATATE whole body PET CT showed no definite dotatate avid focus suspicious for insulinoma. He was discharged on diazoxide but couldn’t tolerate due to side effects. Subsequently patient had distal pancreatectomy and splenectomy. Histology of the mass confirmed grade 2 well differentiated pancreatic linsulinoma with MIB-1,6-10%. Insulinomas, the most common cause of hypoglycemia related to endogenous hyperinsulinism, occur in 1-4 people per million of the general population. Delays in the diagnosis of insulinoma are common because the symptoms usually precede detection of a tumor and there may be misattribution of the symptoms to psychiatric, cardiac, or neurological disorders. Surgical resection is the treatment of choice for insulinomas and offers the only chance for cure.

Points for discussion: Medical therapy to control symptomatic hypoglycaemia Imaging modalities