Hyperaldosteronism Flashcards
What is Hyperaldosteronism?
Increased aldosterone secretion from Zona Glomerulosa of Adrenal Cortex
What are the normal physiological steps that cause the release of Aldosterone? (5 steps)
- Juxtaglomerular cells in Afferent arteriole in kidney sense LOW BP
- Juxtaglomerular cells secrete Renin
- Renin converts Angiotensiongen (from liver) –> Angiotensin I
- ACE converts Angiotensin I –> Angiotensin II (in lungs)
- Angiotensin II stimulates Adrenal glands to release Aldosterone
What is the normal function of Aldosterone? (3 things)
= mineralcorticoid steroid hormone, acts on kidney INCREASE BP by:
- Increase Na reabs @ DCT
- Increase K secretion @ DCT
- Increase H secretion @ CD
What is Primary Hyperaldosteronism (aka Conn’s Syndrome)
Adrenal glands are responsible for too much aldosterone prod
What are the causes of Primary Hyperaldosteronism? (4 things)
- Adrenal adenoma (secreting aldosterone) (most common)
- Adrenal hyperplasia
- Inherited (rare)
- Adrenal carcinoma (rare)
What is Secondary Hyperaldosteronism?
When excessive RENIN is causing adrenal glands to prod more aldosterone
What are the causes of Secondary Hyperaldosteronism? (2 things)
When BP in kidney much lower than rest of body in:
- Renal artery stenosis / obst (athersclerosis)
- HF
What are the CF of Hyperaldosteronism? (5 things)
- Treatment resistant HTN (headache + visual impairment)
- Metabolic alkalosis
- Signs of Hypokalaemia:
- Weakness
- Cramps
- Paraesthesiae (pins n needls)
- Polyuria + Polydipsia
- Pitting oedema (Secondary HA)
- Abd bruits (Secondary HA) (Renal artery stenosis)
(often asymptomatic tho)
What investigations should you do for sus Hyperaldosteronism? (6 things)
- Renin + aldosterone levels
- Adrenal vein sampling
- BP
- UnE
- ABG
- CT / MRI
- Renal doppler US / CT angiogram / MRA (MR angiogram)
What do Renin + aldosterone levels tell you in sus Hyperaldosteronism?
- HIGH aldosterone + LOW renin = Primary Hyperaldosteronism
- HIGH aldosterone + HIGH renin = Secondary Hyperaldosteronism
Why is Renin LOW in Primary but HIGH in Secondary Hyperaldosteronism?
- Primary = high aldosterone will do -ve fdbk = high BP will cause renin to be suppressed
- Secondary = Renin is high bc dis da whole cause of Secondary HA, bc BP in kidney much lower than rest of body
Why is Adrenal Vein Sampling done in Primary Hyperaldosteronism? (3 things)
- To measure Aldosterone levels in both adrenal veins
- Unilateral n Bilateral differentials including: Aldosterone Producing Adenoma (APA) n Bilateral Adrenal Hyperplasia (BAH) etc
- If unilateral disease = can be surgically resected
Why is BP checked in sus Hyperaldosteronism?
To check the effect of high aldosterone
Why should you do UnEs for sus Hyperaldosteronism?
To check for Hypokalaemia
Why should you do an ABG for sus Hyperaldosteronism?
To check for Metabolic Alkalosis
What are the management options for Hyperaldosteronism? (3 things)
- Aldosterone antagonists (Spironolactone) (controls BP + K)
- Surgical removal of Adenoma
- Percutaneous Renal Artery Angioplasty via femoral artery to treat Renal Artery Stenosis
Angioplasty = opening up narrowed artery
