Adrenal Flashcards
What is the makeup of the adrenal glands?
medulla in the middle
cortex around it
What is within the adrenal cortex?
- glomerulosa: mineralocorticoids eg aldosterone
- fasciculata: glucocorticoids eg cortisol
- reticularis: adrenal androgens
What is aldosterone controlled by?
RAAS and plasma K+ so is activated in response to low BP
What is the production of cortisol and androgen controlled by?
regulated by CRH (hypothalamus) and ACTH (anterior pituitary) pathway
What are steroids used for?
- suppress inflammation
- suppress immune system
- replacement for own steroid production
What types of diseases are steroids used to treat?
- allergy
- inflammatory disease
- malignant disease
What are the causes of primary adrenal insufficiency?
- Addison’s
- Congenital adrenal hyperplasia
- TB
- autoimmune
What is the biochemistry of primary adrenal insufficiency?
high ACTH
high Na
high K
What are the causes of secondary adrenal insufficiency?
- lack of ACTH stimulation
- pituitary/hypothalamus disorder
- iatrogenic
- steroid use
What are the features of secondary adrenal insufficiency?
- low ACTH
- pale skin
- treat with hydrocortisone
What is adrenal insufficiency diagnosed with?
synacthen test (works for secondary too as the decreased ACTH leads to atrophy)
What are the ACTH dependent causes of Cushing’s?
- pituitary adenoma
- ectopic ACTH
- ectopic CRH
What are the ACTH independent causes of Cushing’s?
- adrenal adenoma
- adrenal carcinoma
- nodular hyperplasia
Why can you not stop steroids suddenly?
long term steroid treatment suppresses ACTH production so there is adrenal cortex atrophy so the steroids can’t be stopped
What are the cardiovascular actions of aldosterone?
- increase cardiac collagen
- increased sympathetic outflow
- sodium retention
- altered endothelial function
- cytokines and ROS synthesis
