Primary hyperaldosteronism

Question 1

Define primary hyperaldosteronism

Answer 1

Characterised by autonomous aldosterone overproduction from the adrenal gland w/ subsequent suppression of plasma renin activity

Question 2

Causes of primary hyperaldosteronism

2 +2 rare

Answer 2

Adrenal adenoma (Conn’s syndrome) - 70% cases
Adrenal cortex hyperplasia - 30% cases

Rare
Glucocorticoid suppressible hyperaldosteronism
Aldosterone producing adrenal carcinoma

Question 3

Aetiology of primary hyperaldosteronism

3

Answer 3

Excess aldosterone leads to increased Na+ & water retention —> hypertension
Also causes increased renal K+ loss —> hypokalaemia
Renin suppressed due to NaCl retention

Question 4

Epidemiology of primary hyperaldosteronism

hypertension, groups for conns & bilateral

Answer 4

1-2% of hypertensive patients
Conn’s syndrome more common in WOMEN & YOUNG patients
Bilateral adrenal hyperplasia is more common in MEN & presents at OLDER age

Question 5

Presenting symptoms of primary hyperaldosteronism

2 general

Answer 5

Usually ASYMPTOMATIC

Tends to be incidental finding on routine blood test

Question 6

Presenting symptoms of primary hyperaldosteronism - hypokalaemia
(4)

Answer 6

Muscle weakness
Polyuria & polydipsia (nephrogenic DI)
Parasthesia
Tetany

Question 7

Signs of primary hyperaldosteronism on physical examination

2

Answer 7

Hypertension

Complications of hypertension (e.g. hypertensive retinopathy)

Question 8

Investigations for primary hyperaldosteronism

2 groups

Answer 8

Screening

Confirmatory

Question 9

Investigations for primary hyperaldosteronism - screening

4

Answer 9

Low serum K+
High urine K+
High plasma aldosterone concentration
High aldosterone: renin activity ratio

Question 10

Investigations for primary hyperaldosteronism - confirmatory
(5)

Answer 10

Salt loading
Failure of aldosterone suppression after salt loading = primary hyperaldosteronism

Postural test
Measure plasma aldosterone, renin activity & cortisol when patient is lying down at 8am
Measure again after 4hrs being upright
Aldosterone producing adenoma = secretion decreases between 8am & noon
Bilateral adrenal hyperplasia = adrenals respond to standing posture & increase renin production leading to increased aldosterone secretion

CT/MRI

Bilateral adrenal vein catheterisation
Measures adrenal vein aldosterone levels to distinguish between causes

Radio labelled cholesterol scanning
Unilateral uptake in adrenal adenomas
Bilateral uptake in bilateral adrenal hyperplasia

Question 11

Management of primary hyperaldosteronism

3 groups

Answer 11

Bilateral adrenal hyperplasia
Aldosterone producing adenoma
Adrenal carcinoma

Question 12

Management of primary hyperaldosteronism - bilateral adrenal hyperplasia
(5)

Answer 12

Spironolactone
Epleronone can be used if spironolactone side effects intolerable
Amiloride (K-sparing diuretic)
Monitor serum K+, creatinine & BP
ACE inhibitors & CCBs may also be added

Question 13

Management of primary hyperaldosteronism - aldosterone producing adenoma

Answer 13

Adrenalectomy

Question 14

Management of primary hyperaldosteronism - adrenal carcinoma
(2)

Answer 14

Surgery

Post operative mitotane (antineoplastic)

Question 15

Complications of primary hyperaldosteronism

Answer 15

Complications of hypertension

Question 16

Prognosis of primary hyperaldosteronism

2

Answer 16

Surgery may cure hypertension

May make hypertension easier to treat w/ medication