Endocrinology focuses on hormonal system and metabolic health. Learn about the diagnosis and treatment of diabetes, thyroid disorders, and adrenal conditions.
Send us all your questions or requests, and our expert team will assist you.
The clinical presentation of pheochromocytoma is famously variable, earning it the moniker “the great mimic” in medical literature. The symptoms are a direct manifestation of the excess catecholamines acting on various organ systems. Because these hormones regulate heart rate, blood pressure, and metabolism, their unregulated release leads to a constellation of signs that can be mistaken for anxiety disorders, essential hypertension, hyperthyroidism, or cardiac conditions. Some patients may experience paroxysmal attacks—sudden, intense episodes of symptoms—while others may have sustained, chronic issues. A smaller subset of patients may be entirely asymptomatic, with the tumor discovered incidentally during imaging for unrelated issues. Recognizing the nuanced patterns of these symptoms is crucial for early detection and for differentiating this potentially lethal condition from more benign ailments.
The hallmark presentation of pheochromocytoma is often described by a classic triad of symptoms: severe headache, excessive sweating, and palpitations. While not all patients exhibit all three simultaneously, the presence of this triad in a patient with hypertension is highly predictive of a catecholamine-secreting tumor. These symptoms typically occur in spells or “attacks” that can last from a few minutes to an hour. The frequency of these attacks can vary significantly, ranging from multiple times a day to once every few months. As the tumor grows, the attacks often increase in both frequency and severity, significantly impairing the patient’s quality of life.
The headache associated with pheochromocytoma is typically described as severe, throbbing, and bilateral. It often has a sudden onset, reaching peak intensity within seconds to minutes. Unlike tension headaches or migraines, which may have a gradual build-up or are associated with an aura, the pheochromocytoma headache is driven by a rapid surge in blood pressure causing acute cerebrovascular dilation or constriction. Patients often report that the pain is incapacitating and may be accompanied by nausea or visual disturbances. The headache usually subsides as the surge of catecholamines is metabolized and cleared from the circulation.
Sweating, or diaphoresis, in pheochromocytoma patients is often inappropriate for the environmental temperature. It typically involves the upper body but can be generalized. The sweating is profuse and drenching, often occurring simultaneously with the headache and palpitations. This is a result of the thermogenic and sudomotor effects of catecholamines. Following an attack, patients may feel cold or clammy as the perspiration evaporates and the body’s metabolic rate begins to normalize. This symptom can be particularly distressing and socially isolating for patients who experience frequent episodes.
The cardiovascular system bears the brunt of the catecholamine storm in pheochromocytoma. The most consistent clinical sign is hypertension, which may be sustained or paroxysmal. The excess norepinephrine causes intense vasoconstriction, increasing systemic vascular resistance and raising blood pressure. Conversely, epinephrine acts on the heart to increase rate and output. The interplay between these hormones creates a volatile hemodynamic environment that places significant strain on the heart and blood vessels. Long-term untreated exposure can lead to catecholamine-induced cardiomyopathy, heart failure, and stroke.
Hypertension in these patients can present in various patterns. Sustained hypertension mimics essential high blood pressure and is more common in patients with norepinephrine-secreting tumors. Paroxysmal hypertension involves sudden spikes in blood pressure on top of a normal or elevated baseline. These spikes can be extreme, with systolic pressures exceeding 200 mmHg, posing an immediate risk of cerebrovascular accidents or aortic dissection. The variability of blood pressure is a key diagnostic clue; highly labile blood pressure that is difficult to control with standard medications should raise suspicion for a secondary cause like pheochromocytoma.
Paradoxically, despite having high blood pressure, many patients with pheochromocytoma experience orthostatic hypotension—a drop in blood pressure upon standing. This occurs because the chronic vasoconstriction reduces total plasma volume. When the patient stands, the body’s normal reflex to constrict vessels and maintain pressure is impaired or insufficient due to the volume depletion and desensitization of vascular receptors. Patients may complain of dizziness, lightheadedness, or even fainting when rising from a seated or lying position. This combination of supine hypertension and orthostatic hypotension is a distinctive feature of the disease.
Catecholamines are potent regulators of metabolism, promoting glycogenolysis and lipolysis to mobilize energy for the “fight or flight” response. In pheochromocytoma, this constant metabolic drive leads to a hypermetabolic state. Patients may experience unintended weight loss despite having a normal or increased appetite. Glucose intolerance or frank diabetes mellitus can develop because catecholamines inhibit insulin secretion and induce insulin resistance in peripheral tissues. Additionally, the elevated metabolic rate can manifest as heat intolerance and a low-grade fever, further mimicking conditions like hyperthyroidism.
The effects of excess catecholamines extend to the gastrointestinal and renal systems. High levels of epinephrine can decrease gut motility, leading to severe constipation or even pseudo-obstruction of the bowel. Nausea and vomiting are common, particularly during paroxysmal attacks. On the renal front, the intense vasoconstriction can compromise blood flow to the kidneys, potentially activating the renin-angiotensin-aldosterone system and exacerbating hypertension. Some patients may also experience polyuria (excessive urination) or polydipsia (excessive thirst), often related to the hyperglycemic state or electrolyte imbalances induced by the tumor.
The neurological and psychological impact of pheochromocytoma is profound and often leads to misdiagnosis. The physical sensations of a catecholamine surge—racing heart, sweating, tremor, and difficulty breathing—closely mimic the somatic symptoms of a panic attack. Consequently, many patients are initially referred to psychiatrists for anxiety or panic disorder. Patients often report an impending sense of doom or intense anxiety during attacks. Neurologically, apart from headaches, patients may experience tremors, paresthesias (tingling sensations), and visual changes. The distinct difference from primary psychiatric conditions is that pheochromocytoma “panic attacks” are usually not triggered by emotional stress and do not respond to standard anxiolytic treatments.
For many patients, symptom attacks appear to occur spontaneously. However, certain physical and chemical stimuli can precipitate the release of catecholamines from the tumor. Mechanical pressure on the abdomen, such as during palpation, bending over, or straining during a bowel movement, can squeeze the tumor and trigger a release. Certain foods containing tyramine (like aged cheeses) and drugs such as histamine, glucagon, and certain anesthetics or antidepressants can also provoke attacks. Recognizing these triggers is part of the patient’s history-taking and can be instrumental in managing the condition prior to definitive treatment.
Send us all your questions or requests, and our expert team will assist you.
Weight loss occurs because the excess hormones increase the body’s metabolic rate, causing it to burn calories faster than normal even with normal food intake.
Yes, the hormones released by the tumor can inhibit insulin production and increase blood sugar levels, potentially leading to diabetes or glucose intolerance.
A paroxysmal attack is a sudden, intense episode of symptoms such as high blood pressure, headache, and palpitations that starts abruptly and subsides after a short period.
The physical symptoms of adrenaline release—racing heart, sweating, shaking—are nearly identical to those felt during a panic attack, leading to frequent misdiagnosis.
Not always; some patients have constantly high blood pressure, while others have normal pressure that spikes dangerously high only during an attack.
Getting a platelet infusion can be scary, especially if you have health issues. At Liv Hospital, we aim to give top-notch care. We also support
Seeking alternatives to bone marrow biopsy? Discover the latest non-invasive tests that can provide accurate results without the discomfort. Diagnosing and monitoring blood-related conditions often
The final stages of anemia show a big drop in red blood cells and hemoglobin. This leads to symptoms like extreme tiredness, pale skin, short
Age is key when it comes to stem cell donation. Most global registries only accept donors between 18 and 40. Some exceptions allow donors up
We are on the cusp of a revolution in regenerative medicine, thanks to hematopoietic stem cells (HSCs). Hematopoietic stem cells are essential for the formation
Hematopoietic stem cells (HSCs) have changed the game in treating serious diseases. They bring new hope with therapies that work well against cancer, autoimmune diseases,
Leave your phone number and our medical team will call you back to discuss your healthcare needs and answer all your questions.
Your Comparison List (you must select at least 2 packages)
