A 44-year-old obese woman presented to the emergency department complaining of headache, vomiting, shortness of breath, and cough. She had no prior medical problems and had been seen in another ED recently for similar symptoms. She had at that time a CT PE that was normal, and she was discharged home after her symptoms spontaneously resolved. Her symptoms started again suddenly the night before she presented to our ED.
She was diaphoretic, tachycardic (145 bpm), hypertensive (150/125 mm Hg), and forcefully vomiting. She denied chest pain, but an ECG was ordered and showed anterior ST elevation with reciprocal change. Cardiology requested transfer to the catheterization lab, given her exam and ECG.
A head CT prior to transfer showed a meningioma but no acute bleed. She remained tachycardic, diaphoretic, and ill-appearing during her stay in the ED. She presented hypertensive, but her blood pressure dropped to 90/50s and eventually stabilized.
The catheterization found no evidence of coronary artery disease, but she had a significant change in her exam and vital signs. Her respiratory status declined, and she was intubated because of sudden hypoxia and increased breathing effort. Her blood pressure increased, and she was transferred to the ICU for continued care.
Find the diagnosis and case discussion on p. 16.
Pheochromocytomas are rare tumors of the adrenal gland, originating from the chromaffin cells in the adrenal medulla. These cells are responsible for producing catecholamines. The incidence of pheochromocytoma is approximately two to eight per million adults in the general population with a prevalence that is higher in the hypertensive population at 0.1-0.6 percent. (Am J Surg 2011;201:700.) The prevalence of post-mortem pheochromocytomas is 0.05 percent, indicating that many of these tumors are often missed. (Lancet 2005;366:665.)
These tumors are more often diagnosed in a hypertensive population, and the median age for diagnosis is 40 to 50. Inclusion of pheochromocytoma in the differential diagnosis is considered more frequently in people with known genetic predispositions, including von Hippel-Lindau syndrome, multiple endocrine neoplasia type 2, and neurofibromatosis. Approximately 25 percent of pheochromocytomas are diagnosed after incidental discovery with imaging obtained for another purpose. (Lancet 2005;366:665.)
The initial presentation of these patients includes signs such as paroxysmal hypertension, headache, flushing, and diaphoresis. Patients may complain of symptoms such as anxiety, chest discomfort, and hot flashes. The presentation of a pheochromocytoma can mimic many other diseases and symptoms, including pallor, fatigue, hyperglycemia, and vomiting. Severe cases with epinephrine-secreting pheochromocytomas can present with hypotension and shock. (Lancet 2005;366:665.)
The differential remains broad given the generic signs and symptoms seen with a pheochromocytoma. Similar presentations may be seen with sympathomimetic ingestion, anxiety or panic disorder, sepsis, and acute coronary syndrome. Single symptom presentations may present an even wider differential, including migraine headache, renal artery stenosis, menopausal syndrome, and heart failure.
The diagnosis of a pheochromocytoma includes biochemical testing. The most sensitive tests would be plasma-free metanephrines or urinary-fractionated metanephrines because absence of these virtually rule out the presence of a tumor. These biomarkers, however, can be positive in other conditions that result in an elevated circulating level of catecholamines, including heart failure, stroke, and shock. Phentolamine can be used as a quick test in the emergency department to evaluate for pheochromocytoma.
Phentolamine will cause a decrease in blood pressure in patients with pheochromocytoma compared with patients with essential hypertension. Eventually, the initial imaging modality for diagnosis would be a CT scan of the abdomen and pelvis with and without contrast to evaluate for adrenal masses if this tumor is suspected. Diagnosis with an MRI is reserved for pregnant patients, children, and those with contrast allergies. (Lancet 2005;366:665.)
Ultimately, the treatment for a pheochromocytoma is surgical removal of the tumor. These patients can have labile hemodynamics and instability during an operation, however, so they will require medical stabilization of catecholamine production prior to the OR. This includes phenoxybenxzamine or doxazosin for alpha-blockade and eventually beta-blockade after stabilization of the alpha receptors in most cases. (Neth J Med 2014;72:190.) The pretreatment time is usually 10 to 14 days. It is essential for alpha-blockade to be established first for excessive catecholamine production because beta-blockade would result in unopposed alpha receptor activity, which would lead to hypertensive emergency, cardiac arrhythmias, and even death. (Lancet 2005;366:665.)
This patient had paroxysmal hypertension and progression to a hypertensive emergency during her ICU stay, prompting the additional workup and CT scan that led to the diagnosis of pheochromocytoma. She was started on doxazosin and then moved to propranolol. She was taken to the operating room for removal of her right adrenal pheochromocytoma approximately one month after initial presentation.
Share this article on Twitter and Facebook.
Access the links in EMN by reading this on our website or in our free iPad app, both available at www.EM-News.com.
Comments? Write to us at email@example.com.