The suspicion of Pheochromocytoma warrants early specialist referral. In the case of borderline values, some tests warrant repeating. The measurement of metanephrines in a 24 hour urine collection should be used as the primary test for investigation. If possible, patients should not be receiving any anti-hypertensive agents prior to specimen collection. Duration of withdrawal varies with the class of drug.
Consultation is recommended.
1-2 Approximately 10 percent of pheochromocytomas are malignant. In 10 percent of adults and 35 percent of children, pheochromocytomas are extra-adrenal in location. The specificity is over 80 percent. The diagnosis should be considered in any patients with typical symptoms, hypertension refractory to multiple drug regimens, accelerated hypertension, known familial syndromes, paradoxic hypertensive responses to anti-hypertensives, e.g., beta blockers, hypertensive episodes during surgical procedures and incidental findings of an adrenal tumor. Evolving concepts in pathophysiology, diagnosis and treatment of pheochromocytoma.