Endocrine causes of hypertension

Question 1

name 4 causes of 2ry HPTN

Answer 1

• Cushing’s syndrome and other glucocorticoid excess states including chronic therapy
• Pheochromocytoma
  -Primary aldosteronism and other mineralocorticoid excess states (rare)
• Renovascular hypertension

Question 2

commonest cause of secondary hypertension (20%), associated unregulated production of ALDOSTERONE

Answer 2

Primary hyperaldosteronism (Conn Syndrome)

Question 3

What is the function of renin

Answer 3

it is to convert angiotensinogen from the liver to angiotensin I which is further converted to Angiotensin II.

Question 4

what is the function of angiotensin II

Answer 4

Sympathetic
activity
* ADH
* Thirst
act on adrenal gland to aldosterone

Question 5

how does angiotensin and aldosterone lead to HPTN

Answer 5

Angiotensin- thirst, ADH, sympathetic, arteriole constriction
Aldosterone- increases Na+ and H20 reabsorption in distal tubules

high BP has a -ve feedback on renin release

Question 6

Explain in details the mechanism of action.

Answer 6

This happen in the renal distal tubular cells–> ENac – amiloride
lead to sodium reabsorption (hyper) while loss of potassium and H+ in the urine

Question 7

investigation of 1ry HADNsm

Answer 7

• Aldosterone >450pmol/L (posture NB)
• Renin suppressed
  – Aldosterone : Renin ratio
  – Increased in primary hyperaldosteronism
  while in 2ry the high aldosterone is secondary to INCREASE in renin

Question 8

In renal artery stenosis both — and ___ are increased

Answer 8

aldosterone and renin

Question 9

the patient has low renin, aldosterone but have hypertension. This findings are likely to be due to.

Answer 9

Apparent Mineralocorticoid Excess
Something else is mimicking aldosterone
commonly caused by glucocorticoid excess (e.g., Cushing’s syndrome)

Question 10

Cortisol

Answer 10

Antagonises insulin action
* Promotes gluconeogenesis
* Promotes proteolysis

Question 11

Cushing’s Syndrome - Investigations

Answer 11

1. 3 x 24 hour urine collection >485nmol/24
   hours
2. Midnight cortisol - elevated:
    Serum > 100nmol/L;
    Saliva > 4nmol/L
3. Loss of diurnal rhythm

Question 12

What is the primary cause of primary hyperaldosteronism (Conn Syndrome)?
a) Adrenal adenoma
b) Sympathetic stimulation
c) Renin-secreting tumor
d) Renal artery stenosis

Answer 12

A

Question 13

Which of the following is the commonest cause of secondary hypertension?
a) Primary hyperaldosteronism
b) Sympathetic stimulation
c) Renin-secreting tumor
d) Renal artery stenosis

Answer 13

a) Primary hyperaldosteronism

Question 14

Which of the following hormones is involved in the regulation of sodium and water balance in primary hyperaldosteronism?
a) Renin
b) Aldosterone
c) ADH
d) Thirst

Answer 14

b) Aldosterone

Question 15

Which of the following electrolyte abnormalities is commonly seen in primary hyperaldosteronism?
a) Hypokalemia
b) Hyponatremia
c) Hyperkalemia
d) Hypernatremia

Answer 15

a) Hypokalemia

Question 16

What is the typical presentation of primary hyperaldosteronism?
a) Hypertension, hypernatremia, and hyperkalemia
b) Hypotension, hyponatremia, and hypokalemia
c) Hypertension, hypokalemia, and alkalosis
d) Hypotension, hypernatremia, and hyperkalemia

Answer 16

c) Hypertension, hypokalemia, and alkalosis

Question 17

How is primary hyperaldosteronism confirmed?
a) Saline loading test
b) Blood pressure measurement
c) Renin-aldosterone ratio
d) Electrolyte panel

Answer 17

A

Question 18

What is the mechanism of action of aldosterone on the renal tubules?
a) Inhibition of Na+/K+ ATPase
b) Increased reabsorption of Na+ and water
c) Increased secretion of K+ and H+
d) Decreased sodium delivery to renal tubules

Answer 18

b) Increased reabsorption of Na+ and water

Question 19

What distinguishes primary hyperaldosteronism from secondary hyperaldosteronism?
a) Increased renin production
b) Renal artery stenosis
c) Renin-secreting tumor
d) Plasma volume depletion

Answer 19

Increased renin production in 2ry hyperaldosteronism

Question 20

Which hormone is primarily responsible for driving increased aldosterone production in secondary hyperaldosteronism?
a) Renin
b) Aldosterone
c) ADH
d) Thirst

Answer 20

A

Question 21

Which medication is commonly used in the treatment of primary hyperaldosteronism?
a) Spironolactone
b) Amiloride
c) EnaC inhibitor
d) ACE inhibitor

Answer 21

Both spironolactone and amiloride are commonly used medications for managing primary hyperaldosteronism.

Spironolactone is a medication classified as an aldosterone receptor antagonist
Amiloride is a medication that belongs to the class of potassium-sparing diuretics. Its primary mechanism of action involves inhibiting the epithelial sodium channels (ENaC) in the distal renal tubules