Korean J Med.
2012 Oct;83(4):503-509.
A Case of Paroxysmal Pheochromocytoma with Normal Catecholamine Levels
- Affiliations
-
- 1Department of Internal Medicine, Jeju National University Hospital, Jeju National University School of Medicine, Jeju, Korea. okdom@medimail.co.kr
- 2Department of Internal Medicine, Hankook General Hospital, Jeju, Korea.
Abstract
- A 53-year-old woman had a 1.7 cm left adrenal mass on an abdominal computed tomography (CT) scan. She presented with paroxysmal headache, palpitation, sweating, and hypertension. The patient was highly suspected of having a pheochromocytoma, but measurements of 24-hour urinary metanephrine, catecholamines, and vanillylmandelic acid were normal. Plasma and urine catecholamine levels were within the normal range even during paroxysmal episodes. A scintigraphic study with 131I-metaiodobenzylguanidine (MIBG) revealed selective concentration of the radiotracer, corresponding to the CT mass. The patient underwent a left adrenalectomy and the pathological examination confirmed the diagnosis of pheochromocytoma. In this report, we describe a rare case of a symptomatic pheochromocytoma with normal catecholamine levels. Our case illustrates that routine nuclear scintigraphy, such as 131I-MIBG, should be performed even in cases with normal hormonal testing for all patients with high clinical suspicion of pheochromocytoma.