Last week, Dr. Ali Junell presented an interesting case of a patient with neurofibromatosis type 1 who presented with hypertensive emergency and an ischemic stroke. The hospital course was notable for treatment refractory tachycardia and hypertension, so a workup for secondary causes of hypertension was pursued. Initial screen was notable for elevated serum metanephrines and normetanephrines. Subsequent 24 hour urine metanephrines and normetanephrines were also high, prompting adrenal imaging which showed a well-circumscribed left adrenal mass, both of which confirmed the diagnosis of pheochromocytoma.
Ali had some great teaching points about how to go about treating blood pressure in patients with a new diagnosis of pheochromocytoma:
- Start with alpha-blockade (remember, starting with beta blockade can lead to unopposed alpha-adrenergic signaling and severe hypertension!)
- Phenoxybenzamine is preferred, though this patient was switched to a selective alpha blocker (doxasozin) given persistent tachycardia
- Uptitrate alpha-blockade over a course of 3-5 days
- CLINICAL PEARL: success of alpha blockade can be measured with orthostatic vitals!
- THEN start beta blockade cautiously and at a low dose
The definitive treatment of pheochromocytoma is surgical by our colleagues in Endocrine Oncologic Surgery.
Ali’s final teaching point was that there is a high association of pheochromocytoma with genetic syndromes such as VHL, MEN2 and neurofibromatosis. So remember, in patients with known genetic syndromes and difficult to control hypertension, your spidey senses should be tingling for a secondary cause!
References:
Gruber LM, Erickson D, Babovic-Vuksanovic D, et al. Pheochromocytoma and paraganglioma in patients with neurofibromatosis type 1. Clin Endocrinol (Oxf) 2017; 86:141
Radiopedia: Pheochromocytoma
Walther MM, Herring J, Enquist E, et al. von Recklinghausen’s disease and pheochromocytomas. J Urol 1999; 162:1582.