Adrenal Insufficiency and Congenital Adrenal Hyperplasia Flashcards
1
Q
what is the precursor for steroid hormone synthesis
A
- lipid
2
Q
zona glomerulosa is responsive to _____
A
- AGII
3
Q
zona fasciculata is responsive to ____
A
- ACTH
4
Q
what diseases affect the adrenal cortex
what diseases affect the adrenal medulla
A
- atrophy
- hyperplasia
- neoplasms
- autoimmune
- infections
- hemorrhage
- neoplasm
5
Q
cortex is derived from
A
- mesoderm
6
Q
medulla is derived from
A
- neural crest
7
Q
ACTH is derived from
A
- POMC (proopiomelanocortin)
8
Q
further breakdown of ACTH into
what does this do
A
- alpha melanocyte stimulating hormone
- stimulate pigmentation in the skin
9
Q
ACTh works through which secondary messengers
A
- cAMP
- PKA
10
Q
what enzyme in the adrenal cortex is stimulated by AG II
A
- aldosterone synthase
11
Q
is aldosterone production regulated by ACTH
what is it regulated by
A
- no
- renin-angiotensin
12
Q
effects of excess cortisol on the brain
A
- depression
- psychosis
13
Q
effects of excess cortisol on adipose tissue distribution
A
- promotes visceral obesity
14
Q
effects of excess cortisol on endocrine system
A
- decrease LH, FSH, TSH, and GH secretion
15
Q
the problem in primary adrenal insufficiency is where
levels of hormones expected: CRH ACTH cortisol aldosterone RAAS system
A
- adrenal cortex
levels of hormones expected: CRH: elevated ACTH: elevated cortisol : low aldosterone: low RAAS system : elevated
16
Q
most common cause of primary adrenal insufficiency in developed countries
in developing countries (which ones)
A
- autoimmune (Addison’s disease)
- infections (TB, histoplasmosis, HIV)
17
Q
infiltrative causes of primary adrenal insufficiency
A
- metastasis
- amyloidosis, hemochromatosis, sarcoidosis
18
Q
hemorrhage causes of primary adrenal insufficiency
A
- disseminated infections (N. meningitidis) - Waterhouse Friderichsen Syndrome
- anticoagulation
19
Q
drugs that can cause primary adrenal insufficiency
A
- ketoconazole
- rifampin
20
Q
how congenital hyperplasias cause primary adrenal insufficiency
A
- impair cortisol and aldosterone synthesis
21
Q
how adrenal leukosdystrophy causes primary adrenal insufficiency
A
- impair cholesterol transport into adrenal gland
22
Q
what happens in Addison’s disease
what is spared
A
- atrophy of adrenal gland after exposure to destructive antibodies
- the medulla is spared
23
Q
what happens in Waterhouse Friderichsen syndrome
A
- septic due to N. meningitidis
- hypotension with DIC (purpura)
- adrenal hemorrhage
24
Q
features of primary adrenal insufficiency due to elevated ACTH
A
- hyperpigmentation of skin/mucosa
25
features of primary/secondary adrenal insufficiency due to cortisol deficiency
- hypotension
- abdominal pain
- hyponatremia
- hypoglycemia
26
features of primary adrenal insufficiency due to aldosterone deficiency
- hypovolemia
- salt craving (hyponatremia)
- hyperkalemia
- metabolic acidosis
27
features of primary adrenal insufficiency due to adrenal androgen deficiency
- decreased pubic and axillary hair
28
hyponatremia in primary adrenal insufficiency due to _____ and ____ deficiency
- cortisol
| - aldosterone
29
secondary adrenal insufficiency - the problem is where
```
levels of hormones expected:
CRH
ACTH
cortisol
aldosterone
RAAS system
```
- hypothalamus and/or pituitary
```
levels of hormones expected:
CRH: low
ACTH: low
cortisol: low
aldosterone: normal
RAAS system: normal
```
30
causes of secondary adrenal insufficiency
- congenital hypopituitarism
- pituitary/hypothalamic tumors
- pituitary infarct
31
what drugs can cause secondary adrenal insufficiency (this is the most common cause of secondary adrenal insufficiency)
how
- exogenous glucocorticoids
- decreases ACTH through negative feedback
- bilateral adrenal cortical atrophy
32
what granulomatous diseases can cause secondary adrenal insufficiency
- sarcoidosis
| - histiocytosis
33
hyponatremia in secondary adrenal insuffiency is due to ________ deficiency
- ONLY cortisol
34
how do we diagnose adrenal insufficiency
how does it work
- Cosyntropin stimulation test
- give ACTH
- measure cortisol levels
35
in what case would a patient with true secondary adrenal insufficiency have a falsely low normal cortisol response to ACTH
- in acute atrophy of adrenals
| - adrenals take time to fully atrophy
36
what is the peak cortisol concentration that distinguishes between normal adrenal function and adrenal insufficiency
- 18 mcg/dl
37
when can you diagnose adrenal insufficiency without a cosyntropin stimulation test
- when cortisol is CLEARLY low
| - and ACTH is CLEARLY high
38
treatment of primary adrenal insufficiency
what meds
- glucocorticoid replacement (hydrocortisone or prednisone)
- mineralocorticoid replacement (hydrocortisone or fludrocortisone)
WE GENERALLY USE HYDROCORTISONE IV FOR BOTH
39
importance of dosing medications for adrenal insufficiency during stress
- increase dosing
40
treatment of secondary adrenal insufficiency
what meds
- glucocorticoid replacement (hydrocortisone or prednisone)
41
all potencies of glucocorticoids are relative to
potency of prednisolone
potency of prednisone
potency of dexamethasone
- hydrocortisone
- 4.0
- 3.5
- 30
42
what is the physiologic dose of glucocorticoids per day
patients using higher than this are at risk for what when steroids are withdrawn
why?
- 20 mg/day
- secondary adrenal insufficiency
- you're giving the med so you have decreased feedback on ACTH
- decreased ACTH causes pituitary atrophy
43
what from the kidney can stimulate the release of vasopressin
- AG II
44
inheritance of congenital adrenal hyperplasia
- autosomal recessive
45
what is the cause of congenital adrenal hyperplasia
what leads to the hyperplasia
- deficiency of enzyme is steroid synthesis pathway
| - chronically high ACTH production leads to hyper plastic adrenal glands
46
most common enzyme missing in congenital adrenal hyperplasia
- 21-hydroxylase
47
21-hydroxylase deficiency
- aldosterone levels:
- cortisol levels:
- DHEA levels:
- androstenedione levels:
symptoms
treatment
- aldosterone levels: low
- polyuria, volume depletion, hyperkalemia
- cortisol levels: low
- vascular collapse, vomiting, death in infancy
- DHEA levels: high
- androstenedione levels: high
- masculinization of external genitalia in females
- precocious puberty in boys
- glucocorticoid and mineralocorticoid replacement
- glucocorticoid to suppress ACTH
48
11-hydroxylase deficiency
- aldosterone levels:
- cortisol levels:
- DHEA levels:
- androstenedione levels:
important symptoms
treatment
- aldosterone levels: low
- cortisol levels: low
- DHEA levels: high
- androstenedione levels: high
- hypertension due to high 11-deoxycorticosterone
- glucocorticoid to suppress ACTH
- antihypertensives
49
17-hydroxylase deficiency
- aldosterone levels:
- cortisol levels:
- DHEA levels:
- androstenedione levels
why is BP not low
- aldosterone levels: high
- cortisol levels: low
- DHEA levels: low
- androstenedione levels: low
- lack of secondary sex characteristics
- due to excess mineralocorticoids
50
importance of 11-deoxycorticosterone in excess
- promotes fluid and water retention
| - suppressed plasma renin and aldosterone secretion
51
treatment of 17-hydroxylase deficiency
- exogenous hydrocortisone (or other glucocorticoid) to suppressed ACTH production
- induce menses with oral estrogen and progesterone
