🧬 Adrenal Gland Tumors & Secondary Hypertension
The adrenal gland has two distinct zones. Tumors in each zone cause a specific, predictable form of hypertension.
1. Pheochromocytoma (Medulla)
Hormone: Massive surges of Epinephrine & Norepinephrine.
- BP Pattern: Paroxysmal spikes (e.g., 240/140) with normal BP in between.
- HR: Very fast (Tachycardia).
- Key Signs: Sweating, pounding headache, pallor, high blood sugar.
- Treatment: Alpha-blocker (Phenoxybenzamine) FIRST, then Beta-blocker. Never give Beta-blocker alone (unopposed alpha constriction).
2. Primary Aldosteronism (Conn's Syndrome) - Cortex
Hormone: Excess Aldosterone (Retains sodium, excretes potassium).
- BP Pattern: Sustained, severe hypertension.
- HR: Normal or slow (reflex bradycardia).
- Key Signs: Muscle cramps, weakness. Low serum Potassium (Hypokalemia).
- Treatment: Aldosterone Antagonist (Spironolactone or Eplerenone).
3. Cushing's Syndrome (Cortex)
Hormone: Excess Cortisol (mimics aldosterone and upregulates RAAS).
- BP Pattern: Sustained, moderate to severe hypertension.
- HR: Normal or slightly fast.
- Key Signs: Moon face, Buffalo hump, central obesity, purple striae, easy bruising, high blood sugar.
- Treatment: ACE inhibitors (to block RAAS) + Diuretics. Surgical removal of the tumor.
Differential Diagnosis Cheat Sheet
| Feature | Pheochromocytoma | Conn's | Cushing's |
|---|---|---|---|
| BP Pattern | Spikes | Sustained | Sustained |
| Heart Rate | ⬆ High | Normal/Slow | Normal |
| Serum Potassium | Normal | ⬇ Low | Normal/Low |
| Key Sign | Sweating/Pallor | Muscle cramps | Moon face/Striae |
| First Drug | Alpha-blocker | Spironolactone | ACEi + Diuretic |