Secondary hypertension exists when the patient has increased blood pressure (BP) and also has an underlying condition that causes the hypertension ( Viera & Neutze, 2010). Many conditions can generate hypertension as a symptom, including coarctation of the aorta, renal artery stenonsis, thyroid problems, aldosteronism, sleep apnea, Cushing syndrome, certain medications (such as estrogens, herbal supplements, street drugs, NSAIDs, steroids, and psychiatric drugs such as antidepressants, Prozac, lithium, etc.) and other conditions ( Viera & Neutze, 2010).

One specific cause of secondary hypertension is an endocrine disorder, pheochromocytoma, which is a tumor that produces excessive levels of catecholamines, which in turn cause an increase in BP (Sica, 2008). This is a relatively rare cause of secondary hypertension, but because of its relative severity, may be underreported (Sica, 2008).

Generally, pheochromocytoma is characterized by hypertension, headaches, and excessive sweating and palpitations (Sica, 2008). It may also present with other symptoms such as weight loss, paleness, and anxiety or even panic attacks (Sica, 2008). If the hypertension reaches a crisis point, dizziness, flushing, hallucinations, nausea, vomiting, anxiety; these can be stimulated almost at random, including during a physical exam if the underlying tumor is manipulated inadvertently, or if the patient exercises, has a sudden change in posture, or even while the patient eats (Sica, 2008). There may also be CV symptoms including myocardial infarction and myocarditis, arrhythmias, pulmonary edema, and heart failure (Rossi, Seccia & Pessina, 2007). Diagnostic tests for pheochromocytoma include urinary and plasma levels of catecholamines, urinary metanephrines, or urinary vanillymandelic acids. Very elevated levels (as opposed to slightly elevated levels) are indicative of pheochromocytoma (Rossi et al, 2007).