Endocrinology Flashcards
Kallman syndrome
Decreased FSH and LH from decreased GnRH
Anosmia
Renal agenesis in 50%
how to confirm GH deficiency?
no response to arginine infusion
No response to GNRH
Significance of Metyrapone test
inhibits 11-beta-hydroxylase. this decreases cortisol output of adrenal. should cause ACTH levels to rise
failure of GH to rise in response to insulin indicates
GH deficiency
What electrolyte abnormalities inhibit ADHs affect on the kidney?
hypercalcemia and hypokalemia
treatment for nephrogenic DI?
treat underlying cause. hydrochlorothiazide, amiloride, NSAIDS
Acromegaly is almost always caused by a ?
pituitary adenoma
best initial test to evaluate for acromegaly
IGF-1
most accurate test for acromegaly
glucose suppression test. glucose should suppress GHs
why are prolactin levels tested with acromegaly work up?
cosecretion with GH
Treatment for acromegaly?
** PEGVISOMANT: GH receptor antagonist. Inhibits IGF release from liver.
transphenoidal resection of pituitary.
Cabergoline: DA inhibit GH release
Octreotide lanreotide: somatostatin inhibit GH releae
why does hypothyroidism lead to hyperprolactinemia?
extremely high TRH levels with stimulate prolactin secretion
only CCB to raise prolactin level?
Verapamil
What should you NOT do first in any endocrine disorder
MRI of head
When prolactin level is high perform what tests?
thyroid
pregnancy
BUN/Cr (kidney disease elevates prolactin)
LFTs (cirrhosis elevates prolactin)
when should MRI be done for high prolactin levels?
high prolactin confirmed
medications and other 2ndary causes ruled out
patient not pregnant
Management for (high TSH (double normal) and normal T4?
treat with levothyroxine
When TSH is less than double normal what test should you order next?
antithyroid peroxidase/antithyroglobulin
TSH receptor antibodies means
GRAVES disease
Subacute thyroiditis is treated with?
NSAIDS
Painless “silent” thyroiditis treatment?
none
which medication is preferred for hyperthyroidism?
methimazole
best initial therapy for graves opthalmopathy?
steroids. radiation if not responding to steroids. severe cases need compressive surgery
woman presents with thyroid mass. what is first step in management? why?
TSH, T4. If nodule is hyperfunctioning, do not need immediate biopsy because less concerning for malignancy.
Thyroid nodules > ____ must be biopsied with FNA if there is normal thyroid function
1cm
Do you complete ultrasound or radionucleotide scanning in a euthyroid patient with a nodule? why or why not?
No. These tests cannot exclude cancer
What are the 2 mainstays of thyroid nodule management?
- TSH and T4 levels
2. FNA the nodule
what 2 conditions account for 90% of hypercalcemia patients?
primary hyperparathyroidism and cancer
Acute hypercalcemia is treated with?
- saline hydration at high volume
2. bisphosphonate, pamidronate, zoledronic acid
Plicamycin and gallium are OLD therapies for hypercalcemia that are always WRONG on EXAM
always wrong!
When do you use prednisone to treat hypercalcemia?
when its from sarcoidosis or granulomatous disease
if a patient with cancer prsents with hypercalcemia and fluids and bisphosphonates dont control hypercalcemia, what is your next step of therapy
calcitonin
What is the best imaging test for effects of high PTH on bone?
DEXA densitometry
common electrolyte cause of hypocalcemia?
hypomagnesemia (mag is necessary for PTH to be released from gland) low mag also leads to increased urine loss of calcium
for every 1 decrease in albumin, calcium decreases by?
.8
cushing syndrome =
hypercortisolism
cushing disease =
pituitary overproduction of ACTH
what is more specific, 1 mg dex suppression test or 24 hour urine cortisol?
24 hour urine cortisol. there are false positive tests on the 1 mg overnight dex test
Once you find hypercortisolism and ACTH elevation but ACTH doesn’t suppress with dex, what do you suspect, what do you do next?
ectopic production of ACTH + cancer
what tests should you order if you come across an adrenal adenoma incidentally?
metanephrines of blood or urine to exclude pheo
renin/aldo to exclude hyeraldo
1 mg overnight dex suppress
What if you have an ACTH dependent cushing syndrome that is suppressed by high dose dex, you do an MRI and you see nothing?
Petrosal sinus sampling for ACTH (some tumors are too small to see on MRI)
What is the most common cause of hypoadrenalism (addison disease) ?
autoimmune destruction of adrenal gland
causes of acute adrenal crisis?
hemorrhage, surgery, hypotension, trauma, sudden removal of chronic high dose prednisone
common myeloid change in hypoadrenalism?
Eosinophilia
most specific test of adrenal function?
Cosyntropin stim test (synthetic ACTH). measure cortisol level before and after admin of cosyntropin
high BP and hypokalemia =
primary hyperaldo
most accurate test to confirm presence of unilateral adenoma?
sample of venous blood draining the adrenal (should show high aldo)
how do you treat unilateral adenoma of adrenal?
treatment of bilateral adrenal hyperplasia?
- unilateral: surgery laparoscopic
- bilateral hyperplasia: epleronone, spironolactone (aldo antagonists)
side effects of spironolactone
gynecomastia, decreased libido
MIBG scanning is used for?
nuclear isotope scan used to detect location of pheo that originates outside of the adrenal gland
best measure of severity of DKA?
serum bicarb (AKA anion gap)
most common thyroid cancer?
papillary
papillary thyroid cancer spreads by?
lymphoid
follicular thyroid cancer spreads by?
hematologic
type of thyroid cancer found in calcitonin producing C cells.
medullary
diagnosis of osteoporosis is made when?
T score is 2 standard deviations away from a young persons bone mineral density (T score)
Osteopenia
between 1 and 2.5 SDS below normal of a young person
Lab values in osteoporosis
normal calcium, phosphate, parathyroid hormone
Treatment of osteoporosis?
calcium and vitamin D supplementation. smoking cessation and weight bearing exercises . bisphosphonates.
% mortality in the year following a hip fracture?
50%
“mosaic” lamellar bone pattern on x-ray?
Pagets
aching bone or joint pain, headaches, fractures, nerve entrapment, loss of hearing?
Paget disease
lab values of increased alk phos with normal Ca and Phos suggest?
Pagets
causes of hypoparathyroidism
iatrogenic (postsurgical), autoimmune, DiGeorge, Hemochromatosis, Wilsons (infiltrative)
secondary hyperPTH is?
physiologic increase of PTH in response to renal insufficiency. decreased production of 1-25 dihydroxyvitamin D), calcium deficiency or Vit D deficiency.
Tertiary hyperPTH is?
seen in dialysis patients with long standing secondary hyperparathyroid-> parathyroid glands hyperplasia and become autonomous
Weird hand finding in pseudohypoparathyroidism?
Albright hereditary osteodystrophy (shortened fourth metatarsal or metacarpal)
pseudohypoparathyroidism
PTH resistance. Elevated PTH that is ineffective at target organs
Lab values in secondary hyperPTH
elevated PTH, decreased calcium, increased phosphate (when etiology is renal failure)
lab values in 3 hyperPTH
everything elevated
familial hypocalciuric hypercalcemia
inherited disorder due to mutations in calcium sensing receptor in parathyroid and kidneys. Elevated serum Ca levels. But low Ca in urine.
patient is found to have medullary thyroid cancer. what must you test for before performing surgery
VMA and metanephrines as medullary carcinoma of thyroid is associated with MEN2A/2B
MEN 1 is characterized by?
3 Ps
Pancreatic (VIPoma, Gastrinoma, Insulinoma), Pituitary, Parathyroid adenomas
MEN 2A is characterized by?
2 Ps
Parathyriod, Pheo, med thyroid cancer (Ret-proto-oncogene)
MEN 2B is associated with?
1 P
Neuroma, Med thyroid, Pheo
Ret-proto-oncogene
