Endocrinology Flashcards
in what scenario(s) is DHEA tested?
hirsutism
adreal function
what is the dexamethasone suppression test?
dx for cushings
in what scenario(s) is estradiol tested?
amenorrhea
in what scenario(s) is estriol tested?
monitor fetal wellbeing
in what scenario(s) is FSH/LH tested?
disorders of puberty, subfertility, and pituitary etiologies
gastrin is elevated in what condition(s)
zollinger ellison syndrome
pernicious anemia
pyloric stenosis
atrophic gastritis
chronic renal failure
workup for pheochromocytoma
24 hour urine catecholamine test with or without VMA (breakdown of catecholamines) testing
inc plasma catecholamines NOT suppressed by clonidine
mechanisms of hormone action:
second messengers: insulin, NTs
nuclear reactors: steroids, thyroid, sex hormones, retinoids, vit D
if serum prolactin is high, what are next dx steps?
brain MRI
high prolactin but normal brain MRI at this point; what could be causing the exacerbation of the prolactinoma?
estrogen dominance
subclinical hypothyroidism
DI presentation
ADH def from post pit
inc thirst (wakes at night), urination
water deprivation does NOT cause ADH release; urinate regardless of water intake
kidneys cant concentrate urine
thyroid hormone precursor
tyrosine + iodine
herb for hyperthyroid
lycopus
melissa
main concern in graves
cardio complications; why BB are also in early graves tx with other meds
what medication can often cause hypothyroidism?
lithium; screen pts every 6 mo
if you had a pt presenting with what seemed to be a straightforward graves case, but thyroid labs were normal; what ddx would be your next consideration?
pheochromocytoma
dequervains subacute granulomatous thyroiditis
self limited (8-10 weeks) painful inflammation of thyroid
AI, viral
W>M, 10-40
hyperthyroid > hypothyroid > euthyroid
reidel’s thyroiditis
rock hard/woody thyroid
mimics carcinoma
older women
fibrotic thyroid proliferation (may cause hypothyroidism/dyspnea)
causes of goiter
simple: iodine def, too many goitrogens (ca/fluorine in water, bassicae, polluted water)
multinodular: cancer, adenomatous dz
workup goiter
US and thyroid labs
watch palpation pressure; in secretory/hot nodule can induce thyroid storm with pressing too hard
thyroid adenomas
extremely common
most are benign
pressure sx in throat
post meno women
CS AEs
adrenal suppression if dose exceeds adrenal output (TAPER)
avascular necrosis of hip from fat emboli
cushings
hydrocortisone:prenisone ratio
4:1
pheochromocytoma presentation
adrenal medulla tumor of chromaffin cells that secretes catecholamines
triad: palpitations, pounding HA, episodic sweating
HTN, arrythmias, hyperglycemia, hypermetabolism (very similar to graves presentation)
neuroblastoma presentation
childhood (<5) tumor of adrenal medulla chromaffin cells
occur sporadically, born with + usually will be present in utero
large abdominal mass, can be fatal
addisons presentation
hypoadrenalism (AI, TB, fungal)
adrenal medulla unaffected
weakness, fatigue, wt loss, diarrhea/vomiting, hyperpigmentation from inc ACTH (mimics MSH)
low Na, cl, cortisol
high K
causes of cushings (hyperadrenalism)
long term steroids
pituitary adenoma
ectopic ACTH/neoplasm
thyroid carcinoma
adrenal cortex tumor
conn’s syndrome presentation
solitary aldosterone secreting adenoma in adrenal cortex > hyperaldosteronism
low plasma renin and K
high Na and aldosterone
tachycardic, hypertensive
thymic hyperplasia etiology
myasthenia gravis
SLE, Graves, RA
digeorge syndrome
aplasia/hypoplasia of thymus and parathyroid
lack of cell mediated immunity, hypoparathyroidism
dev defects in heart and great vessels
zollinger ellison syndrome presentation
tumor in pancreas secretes gastrin >
peptic ulcers, gastric hypersecretion, malabsorption, diarrhea
60% are malignant
alpha cells of pancrease secrete
glucagon (opp insulin)
beta cells of pancrease secrete
insulin
delta cells of pancrease secrete
somatostain
PP cells of pancrease secrete
pancreatic polypeptide
insulinoma presentation
beta islet cell tumor of pancreas > hypoglycemia (confusion, LOC, stupor), temp relieved by eating
insulin will be high fasting and non fasting, inc c peptide
need pancreas/abdominal imaging CT/US
MEN1 syndrome
DM1
AI to beta islet cells > dec function
insulin dependent
wt loss, wasting, hypotension, hypothermia
HbA1c levels
5.7-6.5 prediabetic/impaired glucose metabolism
> 6.5 diabetes
<7 DM management
5.7 HbA1c is about an avg blood glucose of
126
what do incretins do?
inc insulin secretion
what insulin is long acting?
glargine
what insulin is short acting?
lispro
DKA presentation
ONLY DM1
lack of insulin > acidosis > burns fat > bodywide dump of ketones
lack of tx
MI, CHF
infxn or emotional disturbance (cortisol release)
digestive complaints > acetone breath odor, low BP, high HR > urinary ketone!!!
DKA tx
test for ketones/sugar
ER!! can not do anything outpatient, they will die.
reactive dysglycemia/hypoglycemia
excess insulin tx in T1DM, sulfonylurea, T2DM excessive insulin
hypoglycemic 1-5 hours after eating
calcitonin production and functions
produced in parafollicular cells of thyroid
lowers blood Ca (via kidney), preserves bone Ca
in bone: inhibit resorption, inc Ca resorption by osteoclasts
in kidney/cortex: inc ca/na/k excretion, dec mg excretion
PTH purpose
raise low blood calcium (dec ca excretion via vit D)
PTH vs calcitonin
calcitonin: blood ca DEC, bone ca INC (via kidney)
PTH: blood ca INC, bone ca DEC (via kidney via vit D)
lysis (loss) of bone triggered by
thyroid function, gravity, bone stress, hypocalcemia > stim osteoclasts
osteoclasts leave behind alk phos
blastic (building) of bone is triggered by
alk phos triggers osteoblasts
abnormal serum ca
what are your next steps
ionized calcium > if abnormal: 24 hr urinary ca»_space; if abnormal work up parathyroid, vit d metabolites, consider lytic bone lesions
high PTH = x calcium
high
bisphosphonates MOA, uses, SEs
inhibit osteoclast activity (osteoporosis prev AND tx)
-ronates (alendronate)
orally/by injection
SE: esophagitis, osteonecrosis of jaw
what SERM is used in osteoporosis prev/tx more commonly
SEs
raloxifene
SE: faux menopause
MEN I
kidnety stones, stomach ulcers, sx of hyperparathyroidism and insulinoma
MEN II
medullary thyroid cancer (secretes calcitonin), hyperparathyroidism, pheochromocytoma (pounidng Ha, palpitations, sweats, inc BP)
panhypopituitarism workup
triple bolus test (rapid IV infusion insulin, GnRH, TRH)
how to differentiate between central and nephrogenic DI?
exogenous ACH (desmopressin)
in central, will inc water reabsorption in kidneys
tx nephrogenic DI
HCTZ
tx SiADH
furosemide
gigantism/acromegaly tx
bromocriptine
tx cushing
radiation
primary hyperthyroidism / graves tx
propylthiouracil
BB for sx
hyperparathyroidism presentation
hypercalcemia > bones, stones, groans, psychiatric overtones
causes of acute adrenal insufficiency
abrupt steroid withdrawwl
waterhouse friderichsen syndrome (septicemia from neisseria>hemorrhage), anticoags
addison disease tx
corticoid replacement therapy
