- History of pheochromocytoma. Fractionated metanephrines will be tested in patients with history increasing the risk for a catecholamine secreting tumor (paroxysms of tachycardia, pallor, or headache; personal or family history of MEN 2A, MEN 2B, neurofibromatosis, or von Hippel-Lindau disease; episodic or treatment of refractory hypertension, defined as requiring 4 or more medications to achieve normotension).