Flashcards in Primary and Secondary Hypertension Deck (14):
How many cases of HTN are primary? Secondary?
- primary: 85 - 90%
- secondary: 10 - 15%
What are the two leading causes of Secondary HTN?
- renal disease and primary aldosteronism
Primary Aldosteronism is also known as:
- Conn's syndrome
How can we tell the difference between Secondary HTN due to Renal Disease vs. due to Primary Aldosteronism?
- in renal disease, there will be high aldosterone AND high renin (the renin will cause the aldosterone)
- in primary aldosteronism, there will only be high aldosterone
Other than Renal Disease and Primary Aldosteronism, what are three other causes of Secondary HTN?
- phaeochromocytoma, Cushing's disease, congenital adrenal hyperplasia
- tumor(s) in the adrenal gland, resulting in an increase in adrenaline or noradrenaline
- can lead to paroxysmal/episodic bursts of secondary HTN
- gluco-corticoid excess usually due to an issue with the hypothalamic-pituitary-adrenal axis
- the excess cortisol can lead to secondary HTN
Pathophysiology of Cushing's Disease in the context of a broken hypothalamic-pituitary-adrenal axis.
- hypothalamus secretes CRH, causing the pituitary gland to secrete ACTH, which triggers the adrenal cortex to release cortisol (excess cortisol --> high BP)
What can cause Cushing's Disease?
- prolonged use of corticosteroids (iatrogenic), ACTH hypersecretion from a pituitary adenoma, ectopic ACTH secretion, cortisol hypersecretion from adrenal issue
Congenital Adrenal Hyperplasia
- 95% of cases are due to a 21-hydroxylase deficiency (secondary HTN does NOT occur in these patients)
- 5% are due to an 11-hydroxylase deficiency (secondary HT DOES occur here)
In Primary Aldosterone, what type of cells would you see on histology of the malignant adrenal gland?
- tons of glomerulosa type cells (these cells are responsible for aldosterone secretion)
- adrenocorticotropic hormone
- secreted by the pituitary gland in response to the hypothalamus' CRH
- acts on the adrenal cortex to stimulate release of cortisol
- corticotropin releasing hormone
- secreted by the hypothalamus in response to stress and low blood glucose
- acts on the pituitary gland to stimulate the release of ACTH