John is a 45-year-old HR manager went to the family physician with complaints of periods of severe headache, increased heart beats, sweating, anxiety, and even sense of doom. John said that these attacks usually lasted from few seconds up to about 20 minutes. They started about 3 months ago and recurred every 4 –7 days, then they became more frequent and came every 1-3 days. “I also feel a frequent flank pain for about 6 months. It has been checked but at that time the physicians told me that there was nothing to be concerned about.” added John.

On examination:

• Height: 180 cm, Weight: 94 kg, BMI: 29.0
• BP: 135/85 mmHg, Heart rate: 80/min, Respiratory rate: 18/min, Temperature: 36.9 ⁰C, O₂SAT: 98%
• Costovertebral tenderness on percussion bilaterally.

Based on John’s clinical symptoms what are the organ systems that you would perform a focused assessment and/or ask for specific laboratory tests? (select all that apply)

36 hours later John presents with the emergency department because he feels that the attack is starting now. The findings of  his physical examinations are the following:

• BP: 185/115 mmHg, Heart Rate: 134/min, Respiratory rate: 26/min, Temperature: 37.2 ⁰C, O₂SAT: 94%
• The patient appears anxious and dyspneic. Skin is pale and sweaty.

What are your differential diagnoses after witnessing this periodic attack of high blood pressure, tachycardia, sweating and dyspnea?

John’s laboratory tests showed:

• Blood analysis:
  • CBC:
    • Hemoglobin: 135.5 g/L, Hematocrit: 0.41,
    • RBCs: 4.1 x 10¹²/L, MCV: 91 fL, MCH: 32 pg, RDW: 12.1%, Reticulocytes: 0.9%, ESR: 10 mm/hour
    • WBC: 6.9 x 10⁹/L, (Neutrophils: 3.2 x 10⁹/L, Lymphocytes: 3.7 x 10⁹/L, Basophils: 0.06 x 10⁹/L, Eosinophils: 0.32 x 10⁹/L, Monocytes: 0.8 x 10⁹/L)
    • Platelet counts: 298 x 10⁹/L
  • Na: 139 mmol/L, K: 4.2 mmol/L, Cl: 102 mmol/L, Glucose: 6.1 mmol/L, Creatinine: 98.8 µmol/L, Uric acid: 532 mmol/L
  • Triglycerides: 2.4 mmol/L, Cholesterol: 5.9 mmol/L, HDL: 1.0 mmol/L, LDL: 3.7 mmol/L
  • Bilirubin: 11 mmol/L, Albumin: 43 g / L, AST: 22 U/35L, ALT: 34 U/L
  • TSH: 3.8 µU/mL, Total T₄: 96 nmol/L, Free T₄: 15 pmol/L, Total T₃: 2.6 nmol/L, Free T₃: 5.6 pmol/L
  • Serum cortisol (8 am): 327 nmol/L, Aldosterone (recumbent): 0.22 nmol/L
  • Epinephrine: 943 pmol/L, Norepinephrine: 5664 pmol/L, Dopamine: 523 pmol/L

• Urinalysis:
  • Color: amber yellow, pH: 5.0, Specific gravity: 1024, Osmolarity: 632 mmol/kg; Glucose, Ketones, Albumin, Bilirubin: negative, WBCs and RBCs: 1 and 2/HPF, Epithelial cells, Casts, Bacteria, Yeast: negative, Uric acid crystals: ++
  • Epinephrine: 321 nmol/ 24 hours, Norepinephrine: 932 nmol/24 hours, Metanephrine: 8.4 µmol/24 hours, VMA: 98 nmol/24 hours, Dopamine: 1156 nmol/24 hours, Aldosterone: 22 nmol/24 hours, Cortisol free: 202 nmol/24 hours

What is VMA?

What laboratory findings support the diagnosis of pheochromocytoma in John’s case? (select all that apply)

All the followings statements about catecholamines are correct, EXCEPT: