Test 2 Endocrine Flashcards
What inhibits Growth Hormone and TSH release
Somatostatin
Pitiuitary adenomas DX/TX
dx: MRI
tx: tumor resection
Sx: vision loss/ displopia, H/A
Multiple Endocrine Neoplasia. Tumors are on what endocrine glands?
Pituitary Parathyroid Pancreas GI tumors can cause Zollinger Ellison syndrome- the tumor starts secreting hormones
Acromegaly- Adult
MCC / Sx
excess GH secretion. common cause somatotroph adenoma
Sx: prognathia (big jaw), bossing of forehead, big hands/feet. NO change in height. HTN, cardiomegaly
Acromegaly- Adult
Lab/ TX
labs)
- Increase GH after glucose intake. (normally glucose intake suppresses GH)
- High serum GH & IGF-1 (formed when GH stimulates liver)
Tx: pituitary microsurgery
Gigantism- before puberty
GH hypersecretion before the closing of epipyseal endplates. height affected
Dwarfism Tx
GH deficiency. proportional dwarfism.
tx: recombinant GH
GH deficiency in adults
SX
HYPERlipidemia, HTN, Reduced exercise capacity. change in body comp, metabolism, CV fx, reduced lean body mass.
GH deficiency in adults DX/TX
DX: give GHRH, if evokes GH < 3, then GH deficiency
TX: GH replacement
Prolactinoma si/sx
premenopausal woman: hypogonads= infertility, galactorrhea
Postmenopausal: dx when adenoma gets to big causes vision changes
men: hypogonads, low libido, gynecomastia, galactorrhea
Prolactinoma DX/ TX
dx: if serum prolactin is greater than 20
tx: dopamine agonist (Cabergoline) - decreases serum prolactin and size of adenomas
What inhibits and stimulates Prolactin production
Inhibits: dopamine
Stimulates: TRH
What does Prolactin inhibit?
GnRH …so ultimately this will reduce FSH/ LH
Diabetes Insipidus 2 types
they have increased urination and thirst. Caused by decreased ADH. 2 types:
Central: Post pit has decreased ADH release. Serum ADH will be low
Nephrogenic: kidney resistant to ADH. Serum ADH will be high
Diabetes Insipidus DX/TX
dx: specific gravity <1.005 (dilute) . urine osmolality of <200
tx: desmopressin or argine vasopressin
SIADH
increased ADH secretion, causing dec urination, swelling. dilutional hyponatremia
DX: hyponatremic serum sodium <135 .
Aldosterone what does it do?
secreted by Adrenal Cortex (zona glomerulosa), its a mineralcorticoid. Keeps MAP up, secreted when low BP. Takes in Na (and water), lets K+/H+ out. It is stimulated by increased K+ levels in blood.
Adrenal Insufficiency
Addison’s Disease
lack of aldosterone and cortisol. hyperKalemia (arrythmias), hypoglycemia, hyponatremia, hypotension, salt cravings
Dx: ACTH stimulation test. give cosyntropin to see if prob is at pit or hypothal
Tx: hydrocortisone
Hypercortisolism
sx/dx
increased cortisol secreted from adrenal cortex (zona fasiculata).
sx: moon face, buffalo hump, abdominal purple striae, hair thinning, obesity
dx: high serum cortisol after dexamethasone admin , which normally should shut down cortisol via neg feedback
Hypercortisolism- Cushing syndrome (primary)
prolonged exposure to extreme high cortisol. can be caused by gluccocorticoid drugs or disease.
serum ACTH levels is lower
Hypercortisolism- Cushing disease (secondary)
a tumor in pituitary causes large amts of ACTH
tx: pituitary resection. ACTH will be higher bc cortisol is stimulated by ACTH, so a tumor would hyper secrete ACTH
Pheochromocytoma
tumor in adrenal medulla. secretes Epi/NE.
sx: hypertension, tachyarrthmia, H/A, sweating,
dx: elevated plasma free metanephrines
tx: alpha blockers, calcium channel blockers. removal of pheochromacytoma
What inhibits and stimulates TSH
Inhibits- Somatostatin
Stimulates - TRH
What is the active form of Vit D called
calcitriol
When serum Calcium is high, serum phosphorous is____
low.
vice versa. work in opposites.
Where is calcitonin produced and what does it do?
produced by thyroid gland
It is secreted when Ca level is too high. LOWERS Ca. target is bone (promotes osteoblasts, inhibits osteoclasts) and kidneys (inhibits Ca reabsorption, inc Ca excretion)
PTH is secreted from where and what does it do?
secreted from Parathyroid glands when hypocalcemia
bones: inc osteoclast
kidneys: inc Ca reabsorption, and phosphorous excretion. Activates Vit D to calcitriol
small intestine: INDIRECT action to inc Ca absorption due to calcitriol
You must have enough of this ion to stimulate PTH
Magnesium .
Low Mg could be a result from puking
Normal iPTH values are (serum PTH)
10-65 ng/L
HYPOparathyroid causes
rare.
Iatrogenic, autoimmune, Mg deficiency
HYPOparathyroid symptoms
all related to hypocalcemia
-osteoblasts continue doing their work= brittle bone
-muscle cramps, tetany, impaired muscle contraction/relax
-impaired cardiac contraction/relax
+Chovstek’s sign ( twitch when tap over facial n)
+Trousseau’s sign (wrist/finger flexion after BP cuff inflation)
HYPOparathyroid DDX/ Labs/ TX
DDX: diagnosis made in the absence of CKD
Labs: low iPTH, low serum Ca
Tx: Acute - admit now to ICU
Chronic- take Vit D and Ca, live in sunny place, normalize Mg levels
Hyperparathyroid: primary etiology /cause
older women. people with past neck irradiation
parathyroid itself hyper secretes PTH from pit adenoma
Hyperparathyroid : primary ssx
- inc osteoclast activity- brittle bones
- inc kidney reabsorption and excretion- hypercalciuria and kidney stones
- decreased deep tendon reflex, will have abd pain, constipation, impaired muscle contraction
Hyperparathyroid : primary labs, tx
labs: inc iPTH, inc serum Ca
tx: avoid diuretics like Thiazides, avoid antacids, and too much Vit D, Biphosphates (will decrease PTH activity)
Hyperparathyroid : secondary cause
PTH oversecretes due to long standing hypocalcemia, seen in CKD and in malabsorption ( bariatric surgery)
Hyperparathyroid : secondary ssx/labs/tx
ssx: bone/joint pain
labs: inc iPTH
tx: CKD see nephrologist. bariatric pts take lifelong calcium and vit D
Drugs that cause HYPOcalcemia
Rifampin (for TB) Phenytoin (antiseizure) Furosemide- Loop diuretic inhibits Ca reabsorption Biphosphates- tx for osteoporosis Gluccocorticoids- dec Ca reab
Drugs that cause Hypercalcemia
Thiazide diuretics- Ca reabsorption
Antacid
Vit D intox
Primary hypothyroidism test results
Low T3/T4
High TSH
Secondary Hypothyroid test
low TSH,
low T3/T4
Primary Hyperthyroid test
high T3/ T4
low TSH
Secondary Hyperthyroid test
High TSH
high T3/T4
Normal TSH value
4-5
Causes of Hypothyroid primary/secondary
primary: Autoimmune Hashimotos , iodine def, post surgical
secondary:
Hyperthyroid primary
causes: pregancy, autoimmune Graves, thyroiditis
Thyroid Crisis “storm”
delirium, severe tachycardia, vomit, dehydration, fever
Thyrotoxicosis
sweating, weight change, diarrhea, dehydration, moist skin
Hyperthyroid tx
PTU, Dexamethasone, beta blockers
avoid NSAIDS
hypothyroidism tx
Levo-thyroxine replacement (Synthroid)
Myxedema crisis
sever hypothyroidism- emergency
severe hypothermia, hypotension (CO2 retention), hypoventilation, hypoglycemia
altered mental status is hallmark!
