Primary Aldosteronism Flashcards
1
Q
What is primary aldosteronism?
A
- Excess of aldosterone levels independant of the RAAS axis
2
Q
What are the hallmarks of PA?
A
- HTN
- Hypokalaemia (though often absent)
- Metabolic alkalosis
3
Q
What does PA commonly cause?
A
- Secondary HTN
4
Q
What are the causes of PA?
A
- idiopathic Adrenal Hyperplasia (most common)
- normally bilatera
- Adrenal adenoma (Conn’s syndrome)
- Familiam hyperaldosteronism
- Adrenal carcinoma
5
Q
What are the 3 layers of the adrenal cortex and what hormones do they secrete?
A
- Zona Glomerulosa
- Mineralcorticoid - Aldosterone
- Zona Fasciculata
- Glucocorticoid - Corticosteroid
- Zona Reticularis
- Androgen - DHEA
6
Q
What hormones does the adrenal medulla secrete?
A
- Adrenaline
- Noradrenaline
- Dopamine
7
Q
What cell secretes renin?
A
- Granular cells in juxtaglomerular apparatus
8
Q
Renin will be secreted in response to what?
*remember 3 things
A
- Renal artery hypotension
- Sympathetic stimulation
- Reduced Na levels at DCT
9
Q
What are the function of angiotensin II?
A
- Stimulates adrenal cortex to release aldosterone
- Causes vasoconstriction
- Increases sodium reabsorption
- Stimulates the release of anti-diuretic hormone (ADH)
- Increases sympathetic permissiveness
10
Q
Aldosterone will be released in response to?
*think 3 things
A
- Angiotensin II (primary stimulus)
- ACTH
- Potassium levels
11
Q
What is the primary action of Angiotensin II?
A
- Increase Na channels at DCT
12
Q
What are the clincal features of PA?
* think in the context of HTN & hypokalaemia
A
- HTN
- Asymptomatic (majority)
- If long lasting
- CKD
- CVD
- HF
- Retinopathy
- Hypokalaemia
- Asymptomatic
- Muscle weakness
- Paresthesia
- Mood disturbance
- Polyuria
13
Q
What patients should be screened for PA?
A
- Hypertension and hypokalaemia
- Severe hypertension (systolic > 150, diastolic > 100)
- Hypertension resistant to treatment
- Hypertension and:
- Adrenal incidentaloma
- Sleep apnea
- Family history of early onset hypertension
- Family history of early onset CVA
- Primary aldosteronism affecting all 1st degree relatives with hypertension
14
Q
How would you diagnose PA?
*multi tier testing approach
A
- Screen suspected pt - ARR test
- Confirmatory test
- Oral sodium loading test - aldosterone suppression test
- Identify the test
- CT adrenal glands
- Adrenal vein sampling (gold standard)
15
Q
What are the limitations of CT adrenal glands?
A
- difficult to distinguish adenomas from non-functioning incidentaloma
