Flashcards in Endocrine Deck (107):
LH/FSH deficiency manifestation in men/women
LH/FSH Men: No sperm/testosterone so decrease libido, body hair, ED, and decreased muscle mass.
LH/FSH Women: No ovulation/menstruate normally and become amenorrheic
Children vs. Adults GH deficiency presentation?
Adults-Central obesity, increased LDL+cholesterol, reduced lean muscle mass
Electrolyte finding in panhypopituitarism?
Blood test: Low TSH/thyroxine
Abnormality confirmed with?
Decreased TSH response with TRH
Blood test: Low ACTH/Cortisol
Abnormality confirmed with?
-Normal response to cosyntropin stimulation of adrenal.
-Cortisol will rise (adrenal is normal) in recent disease, but abnormal in chronic disease because of adrenal atrophy.
-No response to ACTH to TRH
Blood test: Low FSH/LH
Abnormality confirmed with?
No confirmatory test
Blood test: GH level low
Abnormality confirmed with?
-No response to arginine infusion or GHRH
Blood test: Prolactin level low?
Abnormality confirmed with?
-No response to TRH
Two electrolyte abnormalities that can cause nephrogenic diabetes insipidus?
Hypercalcemia, hypokalemia. Inhibit ADH effect on kidney
Electrolyte complication of diabetes insipidus?
Hypernatremia; secondary to high-volume urine and volume depletion.
Test to differentiate CDI vs. NDI?
Treatment CDI vs. NDI
NDI-Correct underlying cause; NDI also responds to HCTZ, amiloride, and prostaglandin inhibitors such as NSAID
Most common malignancy with acromegaly?
Colon cancer; growth of underlying colonic polyp
Best initial/most accurate acromegaly?
Most accurate-Glucose suppression test (should normally suppress GH levels)
1) Surgery (trans-sphenoidal resection of pituitary)
-Cabergoline (Dopamine agonist that inhibit GH release)
-Octreotide/lanreotide (Somatostatin inhibit GH release)
-Pegvisomant (GH receptor antagonist, inhibits IGF release from liver)
Why is prolactin tested with GH?
What Ca2+ blocker raises prolactin?
What drugs increase prolactin?
Men/Women presentation of hyperprolactinemia?
-Men-decreased libido, ED (secondary to inhibition of FSH/LH)
-Galactorrhea, amenorrhea, and infertility (secondary to inhibitor of FSH/LH)
4 test for hyperprolactinemia?
1) Thyroid function (hypothyroid leads to increased prolactin)
2) Pregnancy test
3) BUN/creatinine (kidney disease increases prolactin)
4) LFT (cirrhosis elevates prolactin)
1) Dopamine agonists (cabergoline better than bromocriptine)
2) Transphenoidal surgery
3) Radiation is rare
Management of very high TSH (more than double upper limit of normal) vs. high TSH (less than double upper limit of normal)
Very high-Replace hormone
High-1) Antithyroid peroxidase/antithyroglobulin antibodies; if positive than replace!
which disease only has TSH receptor antibodies?
Graves, subacute thyroiditis, painless thyroiditis, exogenous TH use, and pituitary adenoma?
-Graves w/ radioactive iodine
-Subacute thyroiditis w/ aspirin
-Painless thyroiditis w/ NOTHINg
-Exogenous TH w/ stop doing it
-Pituitary adenoma w/ surgery
Tx. graves ophthalmopathy?
Tx. thyroid storm
3) Steroids (decrease peripheral T4-->T3 conversion)
4) Iodinated contrast (blocks peripheral conversion of T4 to more active T3 and blocks release of existing hormone)
Workup of thyroid nodule
1) Perform thyroid function tests (TSH, T4)
2) If tests are normal and >1 cm size, biopsy the gland!
Tx. acute hypercalcemia?
1) Saline hydration
2) Bisphosphonates: pamidronate, zoledronic acid
3) Calcitonin (good for acute symptomatic hypercalcemia not responsive to first 2 options via osteoclast inhibition)
How do you differentiate Primary hyperparathyroid causing hypercalcemia vs. familial hypocalciuria hypercalcemia causing hypercalcemia?
0.02 in Primary Hyperparathyroid and 0.01 in FHH
Best test for bone effects of high PTH?
Tx. Primary hyperparathyroid?
1) Surgical removal STANDARD OF CARE of involved parathyroid
2) When surgery not possible, cinacalcet (allosteric activator of calcium sensing receptor)
3 major causes of hypocalcemia?
1) Mistaken prior parathyroid removal with neck surgery
2) Hypomagnesemia-->decreased PTH release and can also lead to more urinary loss with low Mg levels
3) Renal failure (decreased conversion of 25 OH vit D-->1,25 OH vitamin D)
What is hypoalbuminemia correction with regards to calcium
For every 1 point decrease in albumin, calcium drops 0.8
Best initial test to determine presence of hypercortisolism?
24 hour urine cortisol or 1 mg overnight dexamethasone suppression
Best initial test to determine cause (source) or location of hypercortisolism?
What do you do if MRI does not show a clear pituitary lesion?
Petrosal venous sinus sampling and check ACTH
What tests do you need to do if you randomly came across an asymptomatic adrenal lesion on CT scan?
1) 24 hour urine metanephrines
2) 1 mg overnight dexamethasone suppression
3) Renin and aldosterone levels to exclude hyperaldosteronism
At what dose is it risky to suddenly stop prednisone?
Daily prednisone>20 mg taken for >3 weeks
Patient on chronic steroids undergoes surgery. What is critical to prevent acute adrenal crisis?
Perioperative stress dose of glucocorticoids
Electrolytes and acid/base status in hypercortisolism?
Electrolytes-Hypokalemia and metabolic alkalosis and hypernatremia. Hyperglycemia and hyperlipidemia also present.
Electrolytes and acid/base status in hypocortisolism (eg addisons)?
Electrolytes-Hyponatremia, hyperkalemia, metabolic acidosis. Hypoglycemia also present.
Most specific test for adrenal function?
Cosyntropin (synthetic ACTH) test
Which steroids to you use for adrenal insufficiency (addison)?
-Replace with hydrocortisone
-Fludrocortisone useful if patient has evidence of postural instability b/c of mineralcorticoid of aldosterone like effect
Testing for adrenal insufficiency?
1) Cosyntropin stimulation
2) If cortisol fails to rise, ACTH level?
-low cortisol and high ACTH-->primary (addison)
-Low cortisol and low ACTH --> secondary (glucocorticoids)
Best initial test/most accurate for primary hyperaldosteronism?
Best initial-Plasma aldosterone/plasma renin (increased aldosterone, low renin)
Most accurate-Venous blood draining adrenal (increase aldosterone level)
What test should you never start with in endocrinology?
Tx. of primary hyperaldosteronism?
Unilateral adenoma resected via laparoscopy
Bilateral adenoma-eplerenone or spironolactone
Tx of pheochromo?
Phenoxybenzamine (alpha blocker) before Ca2+ blocker/B-prior to B-blocker
3 tests used to defined diabetes?
1) 2 FBG readings >125
2) Single >200 w/ symptoms (eg polyuria, polyphagia, polydipsia)
How does wt. loss affect DM and insulin?
Wt loss--> less adipose--> less insulin resistance b/c decreased insulin needed for decreased adipose
MOA DPP-IV inhibitors (sitagliptin, saxagliptin, linagliptin, alogliptin)?
Block incretin (increased insulin release and decrease glucagon release from pancrease) METABOLISM.
What are names of incretins?
Glucose-insulinotropic peptite (GIP) and glucagon-like peptide (confusing because it actually suppresses glucagon)
DPP-IV inhibitors/Incretin mimetics side effect?
slow down GI motility. Incretin mimetics also help DECREASE WEIGHT!!
Side effect of glitazones (eg thiazoladinediones)?
Contraindicated in CHF because they increase fluid overload?
Looking for drug with similar MOA to sulfonlyurea but patient has sulfa allergy?
Nateglinide and repaglinide
Alpha glucosidase inhibitors MOA?
Block glucose absorption in bowel. So can cause flatus, diarrhea, and abdominal pain.
Analog of protein called amylin that is secreted normally with insulin. Amylin decreases gastric emptying, decreases glucagon levels and decreases appetite
What electrolyte is used to determine the severity of metabolic acidosis?
Health maintainence diabetes?
Statin >70 LDL
ACEi (BP>130/80 or urine positive for microalbuminuria)
Exam-Eye exam, foot exam for neuropathy and ulcers
Tx. for gastroparesis as complication of DM?
Metoclopramide and erythromycin
Tx. for neuropathy that causes pain?
Pregabalin, gabapentin, TCA
Difference in DKA and hyperosmolar hyperglycemic state in terms of symptoms??
DKA-MORE hyperventilation and abdominal pain along with more rapid onset of hyperglycemic symptoms. LESS prounounced altered mentation. Increased anion gap (
When can you switch fluids from 0.9% NS to 0.5% dextrose?
When can you switch from IV to SQ (basal bolus insulin)?
1) Patient able to eat
2) Glucose 15
When do you add potassium vs hold insulin if potassium is too low?
IV potassium if serum K
When should you consider replacing HCO3-?
Which are best markers indicating resolution of DKA?
Serum anion gap and B-hydroxybutyrate levels
Adverse effects thionamides (eg methimazole, PTU)?
Methimazole-1st semester teratogen, cholestasis
PTU-Hepatic failure, ANCA-associated vasculitis
What dz you treat with radioiodine ablation and what are side effects?
Graves; side effects include permanent hypothyroidism and possible worsening of ophthalmopathy and possible radiation side effects
2 ways to differentiate toxic adenoma vs. graves?
1) No ophthalmopathy
2) Radioiodine uptake in only one are of nodule
What unique lab value may be elevated and be asymptomatic in patients with hypothyroidism?
What is euthyroid sick syndrome?
Fall in total/free T3 levels, with NORMAL levels of T4 and TSH. Due to decreased peripheral 5'-deiodination of T4 due to caloric deprivation, elevated glucocorticoid and inflammatory cytokine levels
When is parathyroidectomy indicated for hypercalcemic patients?
A) symptomatic (eg bones, groans, stones, psych overtone)
B) Age 1 above upper limit normal, DEXA 250)
Best initial/most accurate test for GH levels?
Best initial: IGF-1
Most accurate: 75 g oral glucose load (still shows increased serum GH levels)
What asymptomatic patients need screening for diabetes?
1) Sustained BP >135/80
2) All patients >45
3) ANY age with additional risk factors (eg physical inactivity, first degree relatives, women whose child >9 lb. hx gest dm, HTN, PCOS, dyslipidemia)
3 derangements leading to formation of diabetic foot ulcers?
2) Microvascular insufficiency
3) Relative immunosuppression
What are criteria for metabolic syndrome and how many needed?
1) Abdominal obesity (Men>40, Women>35)
2) FBG>100-110; insulin resistance typical
5) HDL (
clinical electrolyte feature of primary polydipsia?
Desmopressin effect on osmolality if patient has CDI?
Urine osmolality >50% increase
Best screening test for virilizing neoplasm?
Serum testosterone and DHEAS b/c helps delineate site of excess androgen production!
-Elevated testosterone and normal DHEAS-ovarian source
-Elevated DHEAS and normal testosterone-adrenal source
What happens to alkaline phosphotase, PTH, calcium and phosphorum in osteomalacia?
Increase ALP/PTH, decrease calcium and decrease phosphorus
Diagnosis paget disease?
Elevated ALP, normal gamma-glutamyl transpeptidase. Ca2+, phosphorus, PTH all NORMAL.
Tx. paget disease?
What is hypercalcemia due to immobilization?
Iincreased osteocalstic bone resportion increased risk with immobilized patinets
How you differentiate hypercalcemia of malignancy vs. PTH hypercalcemia?
Hypercalemia of malignancy generally have much higher (>13 mg/dL)!!
3 common causes of hypocalcemia?
1) Neck surgery
2) Low Mg2+ (especially in alcoholics)
3) CKD (decreased conversion to 125OHvit d)
Why will vit. D deficiency have low calcium and low phosphate?
Because vit D mediates absorption of both
PCOS diagnostic criteria?
Need 2 of 3
1) Androgen excess: biochemical or clinical (hirsutism, acne, androgenic alopecia)
2) Oligo or anovulation
3) PC ovaries on US>12 follicles
1) Wt. loss
2) Combined OCP
3) Clomiphene citrate
4) Metformin for coexisting DMII
Leydig cell tumor findings?
Yolk sac (endodermal sinus tumor) finding?
-AFP and/or B-hCG elevation
-Elevated Serum AFP
Patient with preexisting Hashimoto thyroiditis at increased risk for what?
Skin side effect of systemic/topical corticosteroids?
Acneiform eruption characterized by monomorphous follicular papules in absence of comedones
What decreases levothyroxine absorption?
Bile acid resins (eg cholestyramine), iron, calcium, aluminum hydroxide, PPI, sucralfate
What increases TBG concentration?
Estrogen (oral), tamoxifen, raloxifen, heroin, methadone
What decreases TBG concentration?
Corticosteroids, androgens, anabolic steroids, slow-release nicotinic acid
What increases thyroid hormone metabolism?
Rifampin, phenytoin, carbamazepine
Patients with positive RET oncogene in setting of MEN undergo what?
What do you need to check when patients come to hospital with new onset AFIB?
Short term (acute) vs. long term (curative) hyperthyroid treatment?
Long-term-->Radioactive iodine ablation; surgery preferrred in pregnant
Secondary (iatrogenic) because of steroid tx.
Symptoms of McCune-Albright syndrome in females?
1) Ovarian cysts, pseudoprecocious puberty, polyostotic fibrous dysplasia of bone, and cafe au lait spots.
Goals of treatment in terms of glucose levels?
What measures can be done to prevent ARF from contrast in patients with diabetes/renal insufficiency?
1) Hydrate patient well
2) Acetylcysteine and bicarbonate (may decrease risk of contrast induced nephropathy)
What is somogyi effect?
Body rxn to hypoglycemia. Too much NPH at dinnertime, so glucose level at 3 AM next morning will be low and body reacts to hypoglycemia with stress hormones that cause high glucose at 7 AM
What is dawn phenomenon?
Hyperglycemia from normal GH secretion in morning. Glucose is high at 7 AM and normal or high at 3 AM so trick is to increase evening (NPH) insulin.
What is risk of giving B-blocker to diabetic?
May mask classic symptoms of hypoglycemia (tachycardia, diaphoresis) which are caused by catecholamine release