Catecholamine excess: pseudopheochromocytoma and beyond.

Symptoms of catecholamine excess or pseudopheochromocytoma can be clinically indistinguishable from pheochromocytoma. Patients usually present with paroxysmal or episodic hypertension and have a negative evaluation for pheochromocytoma. It is important to exclude other causes of catecholamine excess that can be induced by stress, autonomic dysfunction due to baroreflex failure, medications, and drugs. Patients with pseudopheochromocytoma appear to have an amplified cardiovascular responsiveness to catecholamines with enhanced sympathetic nervous stimulation. The exact mechanism is not well understood and increased secretion of dopamine, epinephrine, and norepinephrine, and their metabolites have been identified as potentiating this clinical scenario leading to differing hemodynamic presentations depending on which catecholamine is elevated. Management of this condition is often difficult and frustrating for both the physician and the patient. Most patients respond reasonably well to medications that reduce sympathetic nervous system activity. Anxiolytics, antidepressants, and psychotherapy also play an important role in managing these patients' symptoms.