15.10 Adrenal Cortex

Question 1

adrenal cortex is composed of what three layers?

Answer 1

glomerulosa, fasciciulata, reticularis

Question 2

glomerulosa produces

Answer 2

mineralcorticoids (e.g., aldo)

Question 3

fasiculata produces

Answer 3

glucocorticoids (e.g., cortisol)

Question 4

reticularis produces

Answer 4

sex steroids (e.g., testosterone)

Question 5

What is Cushing syndrome?

Answer 5

Excess cortisol (hypercotisolism)

Question 6

why does Cushing cause muscle weakness with thin extremities?

Answer 6

cortisol breaks down muscle producing amino acids for gluconeogenesis

Question 7

why does cushion cause moon facies + buffalo hump + truncal obesity?

Answer 7

cortisol –> high glucose –> high insulin –> increased storage of fat

Question 8

why does cushing cause HTN?

Answer 8

cortisol upregulates alpha1 recepots on arterioles

Question 9

why does cushing cause osteoporosis?

Answer 9

inhibits osteoblasts, GI ca2+ abs, sex steroids;

increases bone resorption & urine ca2+ loss

Question 10

why does cushing cause immunosuppression?

Answer 10

cortisol inhibits PLA2, IL2, and hist release from mast cells

Question 11

why does cushing cause abdominal striae

Answer 11

impaired synthesis of collagen with thinning of skin

Question 12

6 clinical manifestations of cushing

Answer 12

1. muscle weakness w/ thin extremities
2. moon facies, buffalo hump, truncal obesity
3. abdominal striae
4. HTN
5. osteoporosis
6. immunosuppression

Question 13

how to diagnose cushing

Answer 13

24-hr urine cortisol levels

Question 14

4 causes of cushing

Answer 14

1. exogenous corticosteroids
2. primary adrenal adenoma, hyperplasia or CA
3. ACTH-secreting pituitary adenoma
4. paraneoplastic ACTH secretion (small cell)

Question 15

exogenous corticosteroids –>

Answer 15

bilateral adrenal atrophy bc steroids suppress ACTH secretion (negative feedback)

Question 16

primary adrenal adenoma, hyperplasia, or carcinoma

Answer 16

unilateral adrenal atrophy (of the uninvolved gland)

Question 17

ACTH-secreting pituitary adenoma

Answer 17

bilateral adrenal hyperplasia

Question 18

what could you use to distinguish ACTH secreting pituitary adenoma and paraneoplastic ACTH secretion? (NB: both would result in bilateral hyperplasia)

Answer 18

High-dose dexamethasone

Question 19

high-dose dexamethasone effect on ACTH production by a pituitary adenoma?

Answer 19

DECREASES it (so decreases cortisol)

Question 20

high-dose dexamethasone effect on ectopic ATCH production by a small cell lung carcinoma?

Answer 20

NO EFFECT (so cortisol stays high)

Question 21

what is conn syndrome?

Answer 21

hyperaldosteronism - excess aldosterone

Question 22

conn syndrome presentation

Answer 22

HTN due to sodium retention (maybe - aldo escape with ANP?), hypokalemia, metabolic alkalosis

Question 23

effect of increased aldo

Answer 23

increased sodium reabsorption and K+ secretion by principal cells and increased H+ secretion by alpha-intercalated cells

Question 24

most common cause of primary hyperaldosteronism

Answer 24

sporadic adrenal hyperplasia (adrenal adenoma and carcinoma are less common)

Question 25

hormone levels in primary hyperaldosteronism

Answer 25

``` high aldo low renin (high BP down regulates via negative feedback) ```

Question 26

seen with activation of the RAS system (e.g. by renovascular hypertension or CHF)

Answer 26

secondary hyperaldosteronism

Question 27

hormone levels in secondary hyperaldosteronism

Answer 27

high aldo | high renin

Question 28

excess sex steroids with hyperplasia of both adrenal glands

Answer 28

congenital adrenal hyperplasia

Question 29

most common cause of congenital adrenal hyperplasia

Answer 29

21-hydroxylase deficiency

Question 30

21-hydroxylase is required for the production of what?

Answer 30

aldosterone and corticosteroids

Question 31

21-hydroxylase deficiency causes steroidogensis to be shunted towards

Answer 31

sex steroid prodcution

Question 32

cortisol levels in 21 hydroxylase deficiency

Answer 32

low cortisol --> increased ACTH secretion (loss of negative feedback) --> bilateral adrenal hyperplasia

Question 33

electrolytes and volume status in congenital adrenal hyperplasia

Answer 33

hyponatremia, hyperkalemia, hypovolemia

Question 34

lack of cortisol in 21 hydroxylase deficiency presents how?

Answer 34

life-threatening hypotension

Question 35

congenital adrenal hyperplasia clinical presentation

Answer 35

clitoral enlargement in females or precocious puberty in males due to excess androgens

Question 36

how would you treat congenital adrenal hyperplasia?

Answer 36

cortisol to suppress ACTH

Question 37

lack of adrenal hormones is called

Answer 37

adrenal insufficiency

Question 38

characterized by hemorrhagic necrosis of the adrenal glands, classically due to DIC in young children with N meningitis infection; lack of cortisol exacerbates hypotension, often leading to death

Answer 38

Waterhouse-Friderichsen syndrome

Question 39

chronic adrenal insufficiency due to progressive destruction of the adrenal glands

Answer 39

Addison's dz

Question 40

causes of addison disease

Answer 40

1. AI (west) 2. TB (developed) 3. lung cancer, which loves to metastasize to the adrenals

Question 41

electrolyte and volume abnormalities in addison

Answer 41

hyponatremia, hyperkalemia | hypovolemia, hypotension

Question 42

why do you seen hyperpigmentation in addison?

Answer 42

increased ACTH by productions stimulate melanocytic production of pigment

Question 43

clinical symptoms of addison

Answer 43

hyponatremia + hyperkalemia hypotension + hypovolemia hyperpigmentation weakness, vomiting, diarrhea