Case Presentation:

In our morning report at WCH, we discussed a case of a patient presenting with severe hypertension and episodic headaches. Subsequent laboratory investigation and imaging confirmed the presence of a unilateral adrenal mass which was a pheochromocytoma.

Learning Points:

1. Establishing the diagnosis of hypertension
2. Recognizing the difference between hypertensive urgency and emergency
3. Differential diagnosis of secondary hypertension
4. Diagnosis and management of pheochromocytoma

Establishing the Diagnosis:

CHEP Guidelines

Hypertensive Urgency vs Emergency:

• Urgency=asymptomatic marked BP elevation without target organ damage
• Emergency=marked BP elevation + presence of acute symptoms or progressive target organ damage
  • Brain (Stroke, ICH, encephalopathy)
  • Eyes (hypertensive retinopathy)
  • Heart (MI, CHF, Dissection)
  • Kidneys (hematuria, AKI)

Causes of secondary hypertension:

Pheochromocytoma:

• Risk factors: family history, genetic syndromes (Von Hippel-Lindau disease, MENIIa or IIb, Neurofibromatosis-I)
• Clinical features: “triad” of headache, palpitations, diaphoresis seen only a fraction of the time
• Triggers of episodes: anesthesia, drugs (contrast, glucagon, metoclopramide, TCA, foods/beverages)
• When to consider testing for possible pheochromocytoma:
  • Clinical triad
  • Hyperadrenergic spells (episodic palpitations diaphoresis, headache tremor, pallor)
  • Early onset HTN, resistant HTN, or HTN with new onset DM2 in slender patient
  • Familial syndrome (VHL, MEN, NF1)
  • Adrenal incidentaloma + HTN
  • Paroxysmal HTN with anesthesia/surgery
  • Family History of pheochromocytoma
  • History of gastric stromal tumor or pulmonary chondroma
• Biochemical Testing:
  • Caveat: levels altered by certain drugs and diseases so must take clinical context into consideration and stop drugs, if able
    • Drugs: TCAs, psychotropics, prochlorperazine, decongestants, levodopa
  • 24 hour urinary fractionated metanephrines & catecholamines
  • plasma fractionated metanephrines
  • Note:
    • Metanephrines: metanephrine and normetanephrine
    • Catecholamines: Norepinephrine, epinephrine, and dopamine
• Imaging:
  • Proceed with imaging if biochemical analysis positive
  • CT or MRI
  • If CT or MRI negative (but biochemical positive), possibilities include:
    • Wrong diagnosis (false positive biochemistry)
    • Extra-adrenal mass (i.e. paraganglioma)
      • Evaluate with MIBG scan
      • Other indications for MIBG: very large adrenal mass (higher malignant/metastatic risk)
• Genetic Testing:
  • indicated if:
    • unilateral pheochromocytoma, age <45 years
    • Associated genetic syndrome
    • Extra-adrenal paraganglioma
    • Bilateral pheochromocytoma
    • Unilateral pheochromocytoma with family history
• Management considerations:
  • surgical adrenalectomy (laparoscopic preferred)
  • Preparation for surgery:
    • Start alpha blockade first (phenoxybenzamine or alpha 1 antaongists like doxazosin/terazosin)
      • Then start high salt intake (i.e. 5 g/day)-reverse catecholamine-related volume contraction/prevent CV collapse post-resection
    • Start beta blockade once adequate alpha blockade achieved
      • start low, go slow (risk of CHF due to catecholamine-related cardiomyopathy)
    • Patient to measure home BP BID; target <120/80 seated and sBP>90 standing
  • Perioperative considerations:
    • Hemodynamic monitoring
    • Acute HTN-IV infusion of nitro good option
    • Post-op HoTN: IV fluids
    • Post-op hypoglycemia: IV dextrose-containing solution