Primary hyperaldosteronism

Question 1

Most common cause?

Answer 1

Bilateral idiopathic adrenal hyperplasia is the cause in up to 70% of cases

Question 2

What other causes are there?

Answer 2

• An adrenal adenoma, aka Conn’s syndrome

- An adrenal carcinoma

Question 3

Features?

Answer 3

• hypertension
• hypokalaemia
o e.g. muscle weakness
o this is a classical feature in exams but studies suggest this is seen in only 10-40% of patients
• alkalosis

Question 4

1st line investigation?

Answer 4

Plasma aldosterone/renin ratio (should show high aldosterone levels alongside low renin levels as negative feedback due to sodium retention from aldosterone)

Question 5

Follow up investigations after 1st line?

Answer 5

• high-resolution CT abdomen
• adrenal vein sampling

These are to differentiate between unilateral and bilateral sources of aldosterone excess

Question 6

What does adrenal venous sampling do?

Answer 6

Adrenal Vein Sampling is a procedure where blood samples are taken from both adrenal glands to compare the amount of hormone made by each gland.

Question 7

Managements depending on the causes?

Answer 7

Adrenal adenoma = surgery

Bilateral adrenocortical hyperplasia = aldosterone antagonist e.g. spironolactone