Hyperaldosterone Flashcards
(22 cards)
Conns Syndrome
Excess aldosterone production independent of renin commonly from unilateral adrenal hyperplasia
Cause of primary hyperaldosteronism
Inc Aldosterone
Bilateral adrenal hyperplasia most common
Epidemiology Conns Syndrome
30-50 woman
Most common cause of Secondary hypertension in young adults
Pathophysiology Conns
Excess aldosterone =
↑ sodium retention, ↑ water retention, ↑ blood pressure
Aldosterone also promotes potassium and hydrogen excretion → hypokalaemia and metabolic alkalosis
Presentation Conns
Asymptomatic OR
Resistant HTN,
Hypokalaemia - Muscle cramps, palpitations, constipation / paraesthesia
Metabolic alkalosis
Ix Conns
CORRECT POTASSIUM LEVELS before testing as low K+ suppresses aldosterone
Screening - Plasma aldosterone-to-renin ratio (ARR) ↑ aldosterone, ↓ renin = high ARR confirms suspicion
Confirmation:
Saline suppression test or fludrocortisone suppression test - Aldosterone should normally suppress.
CT adrenal scan to identify adrenal adenoma
Adrenal vein sampling if surgery is being considered — differentiates unilateral vs bilateral disease
BT for Conns
U&Es: look for hypokalaemia
ABG: may show metabolic alkalosis
Mx hyperaldosteronism
Unilateral - Laparoscopic adrenalectomy — can be curative
Bilateral - Medical management with aldosterone antagonists
Correct hypokalaemia before surgery
Examples of aldosterone antagonists
1st Line - Spironolactone
2nd - Eplerenone
Monitoring Conns
Monitor BP, electrolytes, renal function post-op or on meds
Complications Conns
Resistant hypertension
Cardiovascular disease
Hypokalaemia-related arrhythmias
Chronic kidney disease (secondary to hypertension)
Conns Cheat Sheet
Hypokalaemia + hypertension = think Conn’s
Always check aldosterone:renin ratio
2 Hyperaldosteronism
Excess aldosterone secretion due to elevated renin from an extra-adrenal cause
Causes of 2 hyperaldosteronism
Renal artery stenosis (most common)
Renal parenchymal disease
Congestive heart failure
Cirrhosis
Nephrotic syndrome
Dehydration or volume depletion
Pathophysiology 2 Hyperaldosterone
Low renal perfusion =
↑ renin secretion =
↑ angiotensin II =
stimulates adrenal zona glomerulosa to ↑ aldosterone
Aldosterone acts as usual : sodium retention, potassium loss, hypertension
Unlike primary hyperaldosteronism: renin is high
Features of 2 hyperaldosterone
Features of fluid overload or underlying cause
Hypertension (may be severe)
Hypokalaemia (less common or less severe than primary)
Signs related to underlying disease (e.g. abdominal bruits in renal artery stenosis, oedema in heart failure)
Ix 2 hyperaldosterone
Aldosterone level ↑
Renin level ↑
Aldosterone:Renin ratio Low or normal
Imaging -
Renal artery doppler/CT angiography (for stenosis)
Urine sodium - may be low if hypovolemic
Mx 2 hyperaldosterone
Treat underlying cause (e.g., revascularisation for renal artery stenosis)
Medical treatment:
ACE inhibitors or ARBs to block RAAS (avoid in bilateral renal artery stenosis due to risk AKI)
Diuretics to manage volume overload
Mineralocorticoid receptor antagonists (e.g. spironolactone)
Mineralcorticoids
Main hormone: Aldosterone
Produced by: Adrenal cortex (zona glomerulosa)
Primary role:
Regulate electrolyte and water balance
Promote sodium retention and potassium excretion in kidneys
Control blood volume and blood pressure
Effect: Increases blood volume and BP via Na+ and water retention
Receptor: Mineralocorticoid receptor (in kidney distal tubules and collecting ducts)
Glucocorticoids
Main hormone: Cortisol
Produced by: Adrenal cortex (zona fasciculata)
Primary role:
Regulate metabolism (increase gluconeogenesis, protein catabolism, lipolysis)
Modulate immune and inflammatory responses (anti-inflammatory, immunosuppressive)
Help in stress response
Effect: Increase blood glucose, suppress inflammation, affect fat/protein metabolism
Receptor: Glucocorticoid receptor (widely expressed)
Aldosterone Antagonists
Spironolactone / Eplerenone
Block aldosterone receptors in the distal renal tubules
Prevent sodium and water retention
Promote potassium retention (potassium-sparing)
Side effects:
Hyperkalemia (dangerous, monitor potassium!)
Gynecomastia, breast tenderness (mainly spironolactone due to anti-androgen effects)
Menstrual irregularities
GI upset
Monitoring:
Serum potassium and renal function regularly
Avoid in patients with hyperkalemia or significant renal impairment
Indications of aldosterone antagonists
Primary hyperaldosteronism (Conn’s syndrome)
Heart failure (reduce morbidity/mortality)
Resistant hypertension
Cirrhosis with ascites
Certain cases of oedema
