Primary Hyperaldosteronism

Question 1

Define Primary Hyperaldosteronism

Answer 1

Aldosterone production exceeds the body’ requirements and becomes relatively autonomous with regard to the RAAS + subsequent suppression of plasma renin activity

Question 2

Aetiology of Primary Hyperaldosteronism

Answer 2

Excess aldosterone may be secondary to an adrenal adenoma (Conn’s syndrome, 70%)
Hyperplasia of the adrenal cortex (30%)

Rare: glucocorticoid-suppressible hyperaldosteronism or aldosterone producing adrenal carcinoma

Excess aldosterone -> sodium and water retention -> hypertension + increased potassium loss -> hypokalaemia + renin suppression

Question 3

Risk factors for Primary Hyperaldosteronism

Answer 3

20-70
FHx of Primary Hyperaldosteronism
FHx of early onset hypertension and/or stroke

Question 4

Symptoms of Primary Hyperaldosteronism

Answer 4

Usually asymptomatic, picked up on blood stests

Nocturia, polyuria (DI secondary to hypokalaemia)
Lethargy
Mood disturbance: irritability, anxiety, depression
Difficulty concentrating
Paraesthesia, muscles cramps
Muscle weakness
Palpitations

Question 5

Signs of Primary Hyperaldosteronism

Answer 5

Hypertension

Complications of hypertension e.g. retinopathy

Question 6

Investigations of Primary Hyperaldosteronism

Answer 6

Plasma potassium: LOW (or normal)
Aldosterone/renin ratio: raised, >70 (direct active) (aldosterone high, renin low) - stop hypertensives
Fludrocortisone suppression test: failure to suppress aldosterone

Urine potassium: high

Salt loading: failure of aldosterone suppression after sodium load
Postural test: aldosterone and renin levels increase in bilateral adrenal hyperplasia

CT/MRI: visualise any masses
Radio-labelled cholesterol scanning: adrenal adenoma (unilateral uptake), bilateral adrenal hyperplasia (bilateral uptake)

Bilateral adrenal vein catheterisation: distinguish between Conn’s and bilateral adrenal hyperplasia

Question 7

Management for unilateral Aldosterone-secreting tumour

Answer 7

Unilateral laparoscopic adrenalectomy

Immediately before surgery withdraw potassium supplementation + aldosterone antagonsist + antihypertensives

Give post ops IV fluids without potassium

Non-surgical: aldosterone antagonistis e.g. amiloride, spironolactone, eplerenone

Question 8

Management for bilateral aldosterone-secreting tumours

Answer 8

Non-surgical: aldosterone antagonistis e.g. amiloride, spironolactone, eplerenone

Laparascopic adrenalecomy

Question 9

Management for Familial hyperaldosteronism type 1

Answer 9

1. Glucocorticoids e.g. dexamethasone

2. Aldosterone antagonists e.g. amiloride

Question 10

Complications Primary Hyperaldosteronism

Answer 10

Hypertension: stroke, MI, HF, AF, Impaired renal function
Perioperative: bleeding, infection, wound hernia, cardiovascular events
Hyperkalaemia (antagonist action)