Endocrine Abstracts

Introduction: Insulinomas are rare neuroendocrine tumours (NET) derived from the beta islet cell of the pancreas. It is more frequent in women in their fifties compared to men. The diagnosis and treatment of insulinomas in the frail elderly with poor cognition plus multiple comorbidities can be challenging. A delayed diagnosis increases both morbidity and mortality.

Case: An 82-year-old man presented with an episode of confusion and hypoglycaemia (glucose 2.4 mmol/dl). He had been experiencing these symptoms for ten years and weight gain of 20 kg. He was a frail with reduced cognition and dependent on his wife for his activities of daily living. His medical history included pulmonary embolism, polymyalgia rheumatica and hypertension. At presentation he had an elevated c-peptide level of 2.39 nmol/l and insulin level of 287 pmol/l. He declined further investigation but reappeared after having another fall with hypoglycaemia. A subsequent 72-hour fasting test demonstrated hypoglycaemia (2.1mmol/l) with an elevated serum c-peptide (2.17 nmol/l) and proinsulin (25.9 pmol/l). Liver, adrenal and thyroid function were normal. A computerised tomography scan of his abdomen demonstrated a 20-mm solid lesion in the tail of his pancreas, giving a likely diagnosis of an insulinoma. Because of his medical history he was treated conservatively with dietitian input (starch and multiple small meals) and diazoxide. He remains well.

Discussion: This case highlights the challenges and treatment of hypoglycaemia in older individuals with complex medical issues and how crucial it is to consider uncommon causes like insulinoma. Elderly patients often present with atypical symptoms or subtle signs that can easily be overlooked or misinterpreted. Diet and diazoxide can give good symptom control, and somatostatin analogues are an alternative. Surgery can be considered in selective cases with risks and benefits assessed.