Pheochromocytoma diagnosis.

How is Pheochromocytoma diagnosis arrived?

 

  • Symptoms for pheochromocytoma diagnosis
  • Tests for pheochromocytoma diagnosis

Pheochromocytoma diagnosis

Symptoms for pheochromocytoma diagnosis

 

  • “Classic triad” of Pheochromocytoma diagnosis symptoms includes headache, palpitations, and diaphoresis.
  • Paroxysmal spells (5 Ps mnemonic):
    • Pressure: Sudden increase in blood pressure
    • Pain: Headache, chest, abdominal pain
    • Perspiration
    • Palpitation
    • PalloR

  • Additional symptoms of pheochromocytoma diagnosis:

    • Constipation
    • Tremor
    • Weight loss
    • Anxiety
    • Paresthesias
    • Flushing
    • Shortness of breath
    • Nausea/vomiting

Pediatric Considerations in pheochromocytoma diagnosis

Profuse sweating common in children and helps in pheochromocytoma diagnosis

Physical symptoms for pheochromocytoma diagnosis.

  • Hypertension (HTN): Paroxysmal in 1/2 of affected patients; most common clinical sign in pheochromocytoma diagnosis.
  • Tachyarrhythmias
  • Orthostatic hypotension
  • Café au lait spots
  • Lisch nodules of the eye
  • Grade II–IV retinopathy
  • Transient ischemic attacks/stroke
  • Cardiomyopathy
  • Gastrointestinal crisis
  • Diabetes mellitus or insipidus
  • Fever
  • Hypercalcemia
  • Erythrocytosis

Alert after pheochromocytoma diagnosis.

Sudden death may occur in patients with an undiagnosed tumor who undergo surgery or biopsy.

Pheochromocytoma diagnosis  – Tests & Interpretation

Lab for pheochromocytoma diagnosis

Initial lab tests for pheochromocytoma diagnosis

  • Elevated 24-hour urine or plasma metanephrine
  • Elevated 24-hour urine or plasma catecholamines:
    • Blood pressure (BP) must be recorded during plasma sampling for catecholamines. Pheochro-mocytoma cannot be excluded if normal catecholamine values are obtained when the patient is normotensive and asymptomatic (1)[A].
  • Elevated 24-hour urine VMA
  • Plasma catecholamines and metanephrines must be measured when patient is at rest (1)[A].

Follow-Up & Special Considerations for pheochromocytoma diagnosis

  • Drugs that may alter lab results:
    • Increased by:
      • Phenoxybenzamine
      • Tricyclic antidepressants
      • Labetalol
      • Methyldopa
      • Monoamine oxidase inhibitors (MAOIs)
      • Amphetamines
      • Cocaine
      • Clonidine or other drug withdrawal
      • Ethanol or ethanol withdrawal
      • Sotalol
      • Levodopa
      • Acetaminophen
    • Decreased by:
      • Central α2-agonists
      • Reserpine
  • Disorders that may alter lab results: Major physical stress (e.g., surgery, stroke, myocardial infarction, congestive heart failure)

Imaging for pheochromocytoma diagnosis

Initial approach
  • Abdominal image: Magnetic resonance imaging is preferable to computed tomography (CT).
  • I-metaiodobenzylguanidine (MIBG) scan
  • Pentetreotide scan
Alert
When using CT, avoid contrast or protect with adrenergic blockade to avoid precipitating a hypertensive crisis.
Diagnostic Procedures/Surgery
Clonidine-suppression test distinguishes between pheochromocytoma and essential HTN when urine and plasma tests are equivocal.
Pathological Findings
A catecholamine-producing tumor in the adrenal medulla, para-aortic sympathetic chain, wall of the urinary bladder, or sympathetic chain in the neck or mediastinum
Differential Diagnosis
  • Labile essential hypertension
  • Anxiety and panic attacks
  • Paroxysmal cardiac arrhythmia
  • Thyrotoxicosis
    P.993
  • Menopausal syndrome
  • Hypoglycemia
  • Mastocytosis
  • Withdrawal of adrenergic-inhibiting medications
  • Angina
  • Hyperventilation
  • Migraine headache
  • Amphetamine or cocaine use
  • Sympathomimetic ingestion