Endocrine Abstracts

Introduction: Insulinoma is a neuroendocrine tumour derived from the pancreatic islet cells producing excessive amounts of insulin. It can be seen at every age but mostly seen in females above age 50 years old. Because of nonspecific symptoms 20% of cases are misdiagnosed primarily. Major symptoms and signs are related to hypoglycaemia and become significant due to exercise and fasting. This case reveals the diagnostic difficulty due to hypoglycaemia unawareness.

Case report: Mrs. X, 50 years fit and well lady had unexplained falls twice in two years since 2012. First one was in gym while she was exercising. Second episode was a year later, unwitnessed fall with incontinence of urine without tongue bite. She was investigated by cardiologist and neurologist. All investigations including postural BP, ECG, 24 cardiac tape, tilt test, MRI head and EEG were normal. She also lost her driving licence. General practitioner found hypoglycaemia of 2.2 on her routine blood test. Hence he referred her to endocrinology clinic after 27 months since her first episode of symptoms. She was then given a glucometer and diary to check her blood glucose. She was found to have regular hypoglycaemia every day without being aware of it. She was investigated for hypoglycaemia with mixed meal test, which showed Glucose of 2.1 mmol per litre, Insulin-63 pmol per litre and C-peptide-317 pmol per Litre, Anti-insulin antibodies negative. CT abdomen/pelvis confirmed 13 mm hypervascular lesion in the pancreas. She had surgery, partial pancreatectomy. Her blood glucose improved after surgery and she felt very well.

Conclusion: The diagnosis of insulinoma could be delayed due to a variety of non-specific symptoms. Insulinoma is a rare neuroendocrine tumor, usually benign, but can be life-threatening in causing hypoglycemic accidents. Our patient had hypoglycaemia unawareness.