endocrine-adrenal cortex

Question 1

what are the 3 layers of the adrenal cortex

Answer 1

zona glomerulosa
zona fasciculata
zona retircularis

Question 2

what do the 3 zones of the adrenal cortex secrete

Answer 2

zona glomerulosa- mineralcorticoids
zona fasciculata- glucocorticoids
zona retircularis- androgens

Question 3

why do you seen muscle weakness and thin extremeties in Cushing’s syndrome

Answer 3

cortisol breaks muscle producing amino acids for gluconeogenesis

Question 4

why do you see abdominal striae in Cushing’s syndrome

Answer 4

due to impaired synthesis of collagen with thinning of skin

Question 5

Cushing’s syndrome with bilateral atrophic adrenal glands..whats the cause

Answer 5

exogenous corticosteroid use

Question 6

Cushing’s syndrome with unilateral atrophic adrenal gland..whats the cause?

Answer 6

primary adrenal adenoma, hyperplasia or carcinoma

Question 7

Cushing’s syndrome with bilateral hypertrophic adrenal glands..whats the cause?

Answer 7

ACTH secreting pituitary adenoma OR paraneoplastic ACTH secretion

Question 8

how could you tell the difference between an ACTH secreting pituitary adenoma or a paraneoplastic ACTH secreting tumor

Answer 8

high dose dexamethasone (cortisol analog) which suppresses ACTH production by a pituitary adenoma (cortisol levels will decrease) but fails to suppress ectopic ACTH from a paraneoplastic source

Question 9

what is conn syndrome

Answer 9

hyperaldosteronism

Question 10

will you see metabolic acidosis or alkalosis in conn syndrome? why?

Answer 10

metabolic alkalosis because aldosterone causes secretion of H in the distal tubules and collecting duct

Question 11

what is the most common cause of primary hyperaldosteronism

Answer 11

sporadic adrenal hyperplasia

Question 12

in primary hyperaldosteronism, will the renin levels be elevated or depressed

Answer 12

depressed (high BP down regulates renin via negative feedback)

Question 13

when will you see high aldosterone and high renin

Answer 13

in secondary hyperaldosteronism seen with activation of the renin-angiotensin system (ex. in renovascular HTN or CHF)

Question 14

what is the most common cause of congenital adrenal hyperplasia

Answer 14

inherited 21 hydroxylase deficiency

Question 15

production of __ and ___ requires 21 hydroxylase

Answer 15

required for production of aldosterone and corticosteroids

Question 16

what do you see bilateral adrenal hyperplasia in CAH

Answer 16

deficiency of cortisol causes increased ACTH (due to lack of negative feedback)

Question 17

what are the consequences of the increase in the sex steroid production seen in CAH

Answer 17

clitoral enlargement (females) or prcocious puberty (males) due to excess androgens

Question 18

what is syndrome

“hemorrhage necrosis of the adrenal glands classically due to DIC in young children”

Answer 18

waterhouse friderichsen syndrome

Question 19

what infection classically precedes waterhouse friderichsen syndrome?

Answer 19

N. meningitidis infection

Question 20

what is addison’s disease

Answer 20

chronic adrenal insufficiency

Question 21

what is the most common cause of addison’s disease in western countries? developing world?

Answer 21

western countries-autoimmune destruction

developing world-TB

Question 22

what are some clinical features of addison’s disease

Answer 22

hypotension
hyponatremia
hypovolemia 
hyperkalemia
weakness
hyperpigmentation (increased ACTH by products stimulate melanocyte production of pigment
vomiting and diarrhea