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An insulinoma presenting as hypoglycaemia associated with exercise stress testing
Fredolin Lainis1, Eoin Fahy, Matthew Murphy
1Department of Endocrinology, South Infirmary Victoria University Hospital, Cork, Ireland.
BMJ Case Reports
|February 20, 2013
Summary
A 68-year-old man experienced exertional chest pain, later found to be caused by hypoglycemia due to a pancreatic insulinoma. Surgical removal of the insulinoma resolved the symptoms.
Area of Science:
- Endocrinology
- Gastroenterology
- Oncology
Background:
- Exertional chest pain can be a symptom of various conditions, including cardiac and metabolic disorders.
- Hypoglycemia, or low blood glucose, requires thorough investigation to identify the underlying cause.
Observation:
- A patient presented with exertional chest pain, which was initially investigated for acute coronary syndrome.
- Exercise stress testing was stopped due to lightheadedness, prompting a glucose check revealing hypoglycemia (2.2 mmol/l).
Findings:
- A 72-hour supervised fast confirmed hypoglycemia with inappropriately high insulin and C-peptide levels, ruling out sulfonylurea medication as the cause.
- Imaging studies (CT, MRI, endoscopic ultrasound) identified a 2 cm insulinoma in the pancreatic tail.
Implications:
- This case highlights the importance of considering metabolic causes like insulinoma in patients presenting with exertional symptoms and hypoglycemia.
- Successful surgical enucleation of the pancreatic insulinoma resolved the patient's symptoms, demonstrating the efficacy of surgical intervention.
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