Endocrine Abstracts

We present this 62-year-old man with a background of Marfan’s Syndrome, aortic valve replacement, atrial fibrillation and asthma who presented with increasingly severe episodic hypoglycaemia over a period of 22 years. Of note he was not diabetic and was not on any hypoglycaemia-inducing medications. Extensive investigations included the following: 72 hr fast, 5 hr OGTT, continuous glucose monitoring, basic biochemistry, hormone profiles (GH, LH, FSH, testosterone, TFTs, ACTH, SST, cortisol, GH, IGF-1, urinary metanephrines), insulin/c-peptide, screening for inherited metabolic conditions and imaging of his pancreas. Their sole abnormal finding was of significant reactive hypoglycaemia with a plasma glucose level of 2.4 mmol/L at 2.5 hours following a 75 g glucose load. Abdominal ultrasound, abdominal CT scanning and endoscopic ultrasound did not reveal any abnormalities in the pancreas, liver or kidney. A diagnosis of Non-Insulinoma Pancreatogenous Hypoglycaemia Syndrome (NIPHS) was made. Various treatment regimens were implemented including low GI diet, acarbose with some beneficial effects, and later a GLP1 inhibitor with more limited success. Octreotide 50 mcg QDS subcutaneously produced a dramatic decrease in frequency of hypoglycaemia but tachyphylaxis developed despite a dose increase to 100 mcg QDS. Currently he is being treated with a regimen of diazoxide 100 mg tds and prednisolone 20 mg once daily with significant improvement in the number of episodes but with side effects including symptomatic postural hypotension. This case highlights a rare but increasingly recognised form of hypoglycaemia that can be very difficult to treat.