Which of the following manifestations are associated with pheochromocytoma?

Choice A rationale Hypotension is typically not associated with this condition because the tumor hypersecretes catecholamines like epinephrine and norepinephrine. These substances induce potent vasoconstriction and increase systemic vascular resistance, leading to severe hypertension rather than low blood pressure. Patients often experience paroxysmal or sustained elevations in blood pressure that can exceed 200/110 mmHg. Therefore, hypotension would only occur in rare cases of catecholamine depletion or during specific medical crises. Choice B rationale Tachycardia is a classic manifestation resulting from the stimulatory effects of excessive catecholamines on cardiac beta-1 adrenergic receptors. This stimulation increases the heart rate and myocardial contractility significantly. The patient may report a racing heart or a rapid pulse even while at rest. This sympathetic overactivity is a hallmark of the clinical triad, which also includes headache and diaphoresis, and it requires careful monitoring to prevent potential cardiac complications or arrhythmias. Choice C rationale Headaches are one of the most common presenting symptoms and are usually described as severe, pounding, and sudden in onset. This occurs due to the acute and dramatic increase in systemic arterial blood pressure caused by the sudden release of catecholamines from the adrenal medulla or extra-adrenal chromaffin tissue. The resulting cerebral vasodilation and increased intracranial pressure contribute to the intense pain. It is often the symptom that prompts the patient to seek medical evaluation. Choice D rationale Weight gain is unlikely because the chronic excess of catecholamines increases the basal metabolic rate and promotes glycogenolysis and lipolysis. Most patients actually experience unexplained weight loss despite having a normal or increased appetite. The hypermetabolic state induced by the tumor mimics hyperthyroidism in some aspects, leading to increased energy expenditure. Therefore, significant weight gain would be an atypical finding and might suggest a different underlying metabolic or endocrine disorder. Choice E rationale Palpitations occur as a direct result of the chronotropic and inotropic effects of catecholamines on the myocardium. The patient becomes acutely aware of their heartbeat, which they often describe as a forceful thumping or fluttering in the chest. These episodes can occur spontaneously or be triggered by physical exertion, emotional stress, or pressure on the tumor. Palpitations are frequently accompanied by anxiety or a sense of impending doom during a catecholamine surge. Choice F rationale Tremors are caused by the overstimulation of the nervous system and skeletal muscles by circulating epinephrine and norepinephrine. This increased sympathetic tone leads to fine or coarse muscle tremors, often visible in the hands. The excessive stimulation of beta-2 receptors in the skeletal muscles contributes to this fine motor instability. Tremors are frequently associated with other signs of autonomic hyperactivity, such as diaphoresis and nervousness, forming part of the systemic response to the tumor.