Catecholamine and Metanephrine Testing

Pheochromocytomas and paragangliomas are catecholamine-secreting tumors. A pheochromocytoma arises in adrenal tissue; a paraganglioma arises outside the adrenal gland. Their release of epinephrine, norepinephrine, or related catecholamines can be intermittent, so a patient may look well between episodes. Test when the clinical picture suggests catecholamine excess rather than ordering it for uncomplicated hypertension. Suspicion rises with: - Sustained or episodic hypertension that remains uncontrolled despite three or more antihypertensive agents - Hypertensive crises at or above 180/110 mm Hg - Recurrent clusters of headache, palpitations, sweating, and pallor - Hypertension precipitated by a beta-blocker, monoamine oxidase inhibitor, urination, or abdominal pressure - An incidentally discovered adrenal mass - A known hereditary syndrome associated with these tumors, including MEN 2, von Hippel-Lindau syndrome, neurofibromatosis type 1, or an SDHx-related syndrome The symptom cluster matters more than any single symptom. Palpitations and sweating can occur with panic, hypoglycemia, pain, stimulant use, or hyperthyroidism. The concerning pattern is recurrent spells paired with marked blood-pressure instability, pallor, and a trigger history or tumor-risk history. A patient taking several antihypertensives who reports pounding headaches, drenching...