Darrow, pheo, hirsuitism, aldosteronism Flashcards
43 F uncontrolled HTN, rash on wrist, 4th heart sound, K low, HCO3 high,Mg low
acid base state?
hypokalemic alkalosis
if you are hypokalemic how does that affect insulin
decreases insulin secretion leading to glucose intolerance
what type of DI does hypokalemia cayse
nephrogenic because defective activation of renal adenyl cyclase
why is K drawn slowly without vacutainer
fast will cause hemolysis
alubuterol affects on K
lower serum K by stimulating release of insulin
What stimulates the glomerulosa to produce aldosterone
ANG II and K+
what inhibits glomerulosa
ANP= less aldosterone
what stimulates the fasiculata and reticularis
ACTH
what do you expect renin level to be if aldosterone is high
low because neg feedback
what is the standing up test for aldosterone renin
keep patient upright for 3 hours to cause rise in renin
if the aldosterone: renin ratio>30 it is most likely primary hyperaldosteronism
Conns syndrome
primary hyperaldosteronism
causes of conns syndrome
adrenal ademoa
unilateral or b/l hyperlpasia
genetic defect with overly strong effect of ACTH on aldosterone production
what is a good Dx test for primary aldosteronism
24 hour urine collection for aldosterone (>12 confirmatory)
Na loading before
how do you differentiate adenoma from b/l adrenal hyperplasia
postural sitmulation test
what is postural stimulation test
measure aldosterone while patient laying down then walk around 3 hours and if see rise in aldosterone then responding normal so hyperplasia
an adenoma would not respond
how to Tx patient with adrenal hyperplasia causing primary hyperaldosteronisms
meds- spironolactone
licorice effects on adrenals
inhibits 11betaHSD2 which converts cortisol to cortisone
so allows cortisol to drive mineralocortiocoid R leading to HTN and low renin/aldosterone
increased renin and aldosterone with alkalosis could be what
secondary aldosteronism: diuretics, Bartters and Gitelman,
vomiting
nasogastric suction
what are causes of pseudohyperaldosteronisms
liddles
cushings exogenous steroids
CAH
licorice
renin and aldosterone levels in pseduohyperaldosteronism
both decreased
What is liddles syndrome
gain of function in Na channel which inc K secretion and dec aldosterone and renin
pseudohyperaldosteronism
22 y.o F with acne, hirsutism, irregular menses,, acanthosis nigricans and apple shape
lab show inc testosterone with normal DHEA and 17OHP
next test
FSH LH
LH/FSH >2 22 y.o F with hirsutism
problem with follicular cell development in ovaries, Polycycstic ovary syndrome
majority of hirsutism is caused by what
decreased sex hormone binding globulin (increased free testosterone)
if there is not a dec in sex hormone binding globulin what could cause hirsutism
excessive activity of 5 alpha reductase
common causes of hirsutism
PCOS
drugs: pheytoin
idiopathic/familial
common causes virilization
ovarian/adrenal tumors
What labs will you do for PCOS
testosterone, LH/FSH
DHEAS
17 OHP
what labs do you do for CAH
total testosterone, DHEAS, 17OHP all increased
what labs do you do for patients with hirsutism in general
TSH, PRL, IGF-1, 24 hr cortisol, testosterone, DHEAS and 17OHP
in virilization what labs do you want to order
testosterone, DHEA and androstenedioine
ovarian utmor will have what lab results
increased total testosterone with normal DHEAS and 17OHP
adrneal tumor will have what lab results
increased DHEAS
what will lab results be in CAH
total testosterone and DHEAS and 17OHP will be increased
if 17 OHP is >500
CAH
Tx for hirsutism
OCPs with progestins to increase estrogen
antiandroges: spironolactone, flutamide, finasteride, metformin, GnRH agonists
how does insulin affect androgens
triggers ovarian androgen production and reduces SHBG
what occurs in 21 hydroxylase deficiency
shift to zona reticularis
masculinizaiton and hypotension
what occurs in 17 hydroxylase deficiency
shift to the glomerulosa, alot of aldosterone, HTN
what happens in 11 beta hydroxylase deficiency
HTN and masculinization
how does congential adrenal hyperplasia happen
lose cortisol negative feedback so massive increases of androgens with no feedback from cortisol to hypothalamus or pituitary
palpitations, sweating, HA
pheochromocytoma
cafe au lait spots and nodules
neurofibromas
Causes of non-essential HTN
aldosteronism myxedema hyperCa pheo steroid excess
how does epi/norepi produce neutrophilia
mobilization of neutrophils form vessel walls
how does epi/norepi produce hyperglycemia
activation of alpha 2 R on islet beta cells with decreased insulin output and icnreased liver glucose production by beta 2 R
how does epi/noreepi lead to hypotension
vasodilation Beta 2 R
pheo can cause hyperCa how
releases PTHrP
where are tumores that secrete norepi
anywhere in paraganglion chain
where are epinephrine tumors
adrenal gland
what is a good test for pheo
meta iodobenzylguanadine scintography because pheo takes it up
10% pheo
b/l 10%malignant
when must you investigate incidentalomas
25% incidence of having cancer cells if above 6cm so need biopsy if above this size
what is a preoperative evaluation for incidentaloma
plasam free metaneprhines
1 mg DXM suppression to rule out cushings (low dose DXM)
60% incidentalomas associated with
some degree of CAH
causes of facial flushing
carcinoid, medullary carcinoma of the thyroid
pheochromocytoma
