L21- Endocrine Pathology III (adrenal)

Question 1

Adrenal Gland:

• (1) cortex layers / composition
• (2) medulla composition

Answer 1

1:
Zona Glomerulosa: mineralocorticoids, aldosterone
Zona Fasciculata (75%): glucocorticoids, cortisol
Zona Reticulata: sex steroids, estrogen, androgen

2: chromaffin cells (80%Epi, 20%NE)

Question 2

Cortisol:

• (1) protein effect
• (2) lipid effect
• (3) carbohydrate effect

Answer 2

1- degradation
2- lipolysis
3- promotes hyperglycemia via insulin antagonism + inc gluconeogenesis

Question 3

Cortisol:

• (anti-/pro-)inflammatory
• enhances (2) activity (other hormones)
• weak (3) properties / activity
• associated strongly with (4)

Answer 3

1- anti-inflammatory
2- glucagon, catecholamines (SNS)
3- mineralocorticoid
4- stress

Question 4

Aldosterone function

Answer 4

• inc Na, H2O absorption in kidney
• in exchange for (net loss) K+/H+

-inc with dec BP (dec with inc BP)

Question 5

Androgen (adrenal)
1- made in (small/large) amounts
2- excess production results

Answer 5

• small amounts

- excess production –> precocious puberty (boys) OR masculinizing effects in women

Question 6

Estrogen (adrenal)
1- made in (small/large) amounts
2- excess production results from

Answer 6

• small amounts

- rare estrogen producing tumor

Question 7

Cortisol is mostly found as _____ in serum

Answer 7

protein bound to CBG (95%)

Question 8

Aldosterone is mostly found as _____ in serum

Answer 8

60% bound to albumin

Question 9

Adrenal androgens / estrogens are bound to _____ in serum

Answer 9

SHBG- sex hormone binding globulin

Question 10

cortisol and testosterone levels in women are partially influenced by…..

Answer 10

concentration binding proteins

Question 11

describe release of ACTH

Answer 11

Circadian:

• highest in morning
• lowest at mid-night

Note- stress can override circadian rhythm

Question 12

list main and alternate stimulators of Aldosterone

Answer 12

• RAAS / low BP / low renal perfusion
• SNS, high [K+]
• NOTE- NO effect via ACTH

Question 13

what are the types of adrenal cortex diseases

Answer 13

Under-activity: adrenocortical insufficiency

Over-activity: Cushing’s, hyperaldosteronism

Question 14

Primary adrenal insufficiency = (1):

• (2) main cause
• (3) and (4) are other causes

Answer 14

1- Addison disease
2- Autoimmune (60-70%)
3- Infections
4- bilateral secondary carcinoma

Question 15

describe the distribution Addison disease caused by autoimmune

Answer 15

(primary adrenocortical insufficiency)
-can affect just adrenal gland
OR
-in association with other autoimmune diseases: thyroid, type I DM, prematyre ovarian failure

Question 16

list the infections that can cause Addison disease

Answer 16

(primary adrenocortical insufficiency)

TB, AIDS, meningitis –> hemorrhage and destruction of adrenal glands

Question 17

what are the causes of secondary adrenal insufficiency + clinical presentation

Answer 17

-pituitary disorders

No association with hyperpigmentation (low ACTH), electrolyte disturbances (aldosterone not controlled by ACTH)

Question 18

Addison disease clinical features

Answer 18

(primary adrenocortical insufficiency)

• tiredness, weakness
• anorexia, apathy
• abdominal pain
• hyperpigmentation (excess ACTH)
• postural hypotension

Question 19

define adrenal crisis

Answer 19

• often precipitated by infection in patient with adrenocortical insufficiency
• causes circulatory shock, volume depletion, anorexia, n/v

Question 20

List the serum levels of electrolytes, morning cortisol levels, ACTH levels, RAAS components in adrenal insufficiency

Answer 20

Na+ low
K+ high
HCO3- low
glucose low
urea high

• cortisol low / normal
• high ACTH (Addison disease)
• high renin, low aldosterone

Question 21

describe Short Synacthen test

Answer 21

• administer ACTH, 15-30 minutes of infusion
• adrenal glands should release x2-5 times basal cortisol output
• failure of response => Addison disease

Question 22

Addison disease management

Answer 22

(primary adrenocortical insufficiency)

• Replace Glucocorticoids - Prednisolone
• Replace Mineralocorticoids - Fludrocortisone

Question 23

Waterhouse-Friderischsen Syndrome:

• (1) definition
• (2) cause
• associated with (3) manifestations and (4) presentation

Answer 23

1- acute adrenal insufficiency due to bilateral adrenal hemorrhage
2- meningitis (N. meningococci, Pseudomonas spp.)
3- Sepsis, DIC
4- rapidly progressive shock, hypotension, rash (petechiae, purpura), possibly FATAL

Question 24

Hyperadrenalism = _____ + list causes

Answer 24

Cushing Syndrome

• exogenous steroids
• pituitary dependent (ACTH secreting tumor - Cushing disease)
• primary adrenal neoplasm (cortisol secreting adenoma)
• ectopic ACTH

Question 25

differentiate Cushing Syndrome and Disease

Answer 25

Disease: secondary hyperadrenalism via ACTH producing secreting tumors Syndrome: primary, many causes

Question 26

Clinical features of Cushing syndrome

Answer 26

****-Moon facies, Truncal obesity, Buffalo hump - HTN - thin limbs, muscular weakness - purple striae, fragile skin - impaired glucose tolerance - psychiatric disturbances - menstrual disturbances - dec immunity

Question 27

describe the process of a Cushing Syndrome Dx

Answer 27

(must exclude exogenous glucocorticoids) 1) establish presence of hypercortisolism (morning levels) 2) determine source of cortisol 3) check metabolic derangements in association with Cushing syndrome

Question 28

describe the screening tests for Cushing syndrome

Answer 28

24hr Urine free cortisol (most common) 1mg Overnight Dexamethasone (cortisol like): administer at 11pm, measure cortisol at 8am, should be <50 Late-night serum salivary cortisol

Question 29

In diagnosing Cushing Syndrome, indicate the differentiating results in the following tests: - (1) Plasma ACTH - (2) High Dose Dexamthasone suppression test (8mg) - (3) MRI/CT scan - (4) IPSS

Answer 29

1- low ACTH --> adrenal gland tumor /// high ACTH --> pituitary tumor or ectopic tumor 2- cortisol suppression to <50% baseline indicates pituitary source of ACTH over ecotpic source 3- localization of tumor 4- (inferior petrosal sinus sampling) identifies source of ACTH secretion (if not found on MRI)