Adrenals I Flashcards
zones of adrenal Cx
zona glomerulosa
zona fasciculata
zone reticularis
zona glomerulosa makes what
mineralocorticoids- aldosterone
zona fasciculata produce what
glucocorticoids- cortisol
zone reticularis produce what
sex steroids like estrogens and androgens
what does the adrenal medulla make
chromaffin cells which secrete catecholamines like epinephrine
3 syndromes of adrenal hyperfunction
cushin syndrome- excess cortisol
hyperaldosteronism- excess aldosterone
adrenogenital or virilizing syndrome- excess androgens
central obesity, moon facies
abdomina striae
cushings
majority cases of cushins from
administration of exogenous glucocorticoids “iatrogenic”
endogenous causes of cushings
ACTH dependent
ACTH independent
what are the ACTH dependent causes of cushings
pituitary adenoma-cushing disease
ectopic corticotropin syndrome
what are the ACTH independent causes of cushings
adrenal adenoma adrenal carcinoma macronodular hyerplasia primary pigmented nodular adrenal disease McCune Albright syndrome
most common cause of endogenous hypercortisolism
ACTH secreting pituitary adenoma
Cushing disease affects men or women more
women
secretion of ectopic ACTH leading to Cushing syndrome is from what typ of tymors
many nonpituitary
most being small cell carcinoma in lung
most common causes ACTH independent cushing
adrenal adenoma and carcinoma
what lab values will you find with ACTH independent cushing syndrome
elevated cortisol and low ACTH
what changes will you see morphologically in pituitary in cushings
crooke hyaline change- accumulation of intermediate keratin filaments in the cytoplasm
ACTH dependent cushing syndrome will cause what changes in adrenal
nodularity and diffuse hyperplasia
adrenocortical adenomas look like what
yellow tumors surrounded by thin capsules
what do carcinomas assoc with cushing look like
unencapsulated masses taht are large and have all anaplastic characteristics of cancer
early stages of cushing syndrome
HTN and weight gain
buffalo hump
cushing
hypercortisolism affects muscles how
selective atrophy of fast twitch (type 2) myofibers
resulting in decreased muscle mass and proximal limb weakness
how do glucocorticoids cause hyperglycemia, glucosuria and polydipsia
induce gluconeogenesis and inhibit the uptake of glucose by cells
how do glucocorticoids cause thin fragile skin that is easily bruised
loss of collagen and resorption of bones
what mental disturbances do glucocorticoids cause
mood swings, depression, frank psychosis
Dx cushing
24 urine free cortisol concentration is increased
loss of normal diurnal pattern of cortisol secretion
DXM suppression test
what is DXM test
give DXM and then measure corticosteroid level
-if ACTH cannot be suppressed by low dose DXM but - at high dose DXM pituitary can respond and reduce ACTH then know is pituitary cushing syndrome
if cortisol does not decrease with high or low doses DXM what is it
ectopic ACTH secretion
When Cushing is from adrenal tumor what will ACTH level be
low because of feedback inhibition of the pituitary
in adrenal tumor cushing what will results of high and low DXM test be
fail to suppress cortisol excretion
high ACTH with no suppression after high DXM
CT to rule out ectopic ACTH
high ACTH with suppression after high DXM
cushing disease, need MRI
bilateral cortical atrophy of adrenals is a feature of what
exogenous steroid induced disease
what causes primary hyperaldosteronism
autonomous overproduction of aldosterone with suppression of RAAS and decreased plasma renin
most common manifestation primary hyperaldosteronism
bp elevation
most common cause primary hyepraldosteronism
b/l idiopathic hyperaldosteronism
what is the most common adrenocortical neoplasm
aldosterone producing adenoma
conn syndrome
solitary aldosterone secreting adenoma
conn syndrome gender distribution
more common W:M 2:1
mutaiton in glucocorticoid-remediable hyperaldosteronism
rearrangement on chromosome 8 that places CYP11B2 (encodes aldosterone synthase)
what can lead to increased levels of plasma renin
decreased renal perfusion
arterial hypovolemia and edema
pregnancy
<2cm solitary mass buried in adrenal gland
bright yellow on cut section with uniform cells
spironolactone bodies
aldosterone producing adenoma
what will the contralateral adrenal gland look like if one has aldosterone producing adenoma
not atrophic
consequences of hyperaldosteronism
L ventricular hypertrophy and reduced diastolic volumes
increased risk stroke and MI
Dx primary hyperaldosteronism
elevated ratios of plasma aldosterone concentration to plasma renin activity
then need an aldosterone suppression test to confrim
