Not So Incidental: Pheochromocytoma in an Adult with Unrepaired Cyanotic Heart Disease

Pheochromocytoma, a rare neuroendocrine tumour, is often encountered in the general internal medicine clinic as an adrenal incidentaloma. Even rarer is its presence in adult cyanotic heart disease, although there are a few documented reports of this association in various paediatric populations, with chronic hypoxia being the likely driving force. Here we present the case of a 38-year-old adult with unrepaired complex cyanotic congenital heart disease with biochemically proven pheochromocytoma presenting as an adrenal incidentaloma to a general internal medicine clinic. LEARNING POINTS: There is an association between pheochromocytoma and congenital cyanotic heart disease. It is important to maintain clinical vigilance for laboratory testing for pheochromocytoma in patients with cyanotic heart disease who are seen at general internal medicine clinics.