Primary Hyperaldosteronism Flashcards
Define Primary Hyperaldosteronism
Aldosterone production exceeds the body’ requirements and becomes relatively autonomous with regard to the RAAS + subsequent suppression of plasma renin activity
Aetiology of Primary Hyperaldosteronism
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
Risk factors for Primary Hyperaldosteronism
20-70
FHx of Primary Hyperaldosteronism
FHx of early onset hypertension and/or stroke
Symptoms of Primary Hyperaldosteronism
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
Signs of Primary Hyperaldosteronism
Hypertension
Complications of hypertension e.g. retinopathy
Investigations of Primary Hyperaldosteronism
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
Management for unilateral Aldosterone-secreting tumour
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
Management for bilateral aldosterone-secreting tumours
Non-surgical: aldosterone antagonistis e.g. amiloride, spironolactone, eplerenone
Laparascopic adrenalecomy
Management for Familial hyperaldosteronism type 1
- Glucocorticoids e.g. dexamethasone
2. Aldosterone antagonists e.g. amiloride
Complications Primary Hyperaldosteronism
Hypertension: stroke, MI, HF, AF, Impaired renal function
Perioperative: bleeding, infection, wound hernia, cardiovascular events
Hyperkalaemia (antagonist action)