Kaplan- Endo Flashcards
stopped just before 31
a 52 y.o. woman with heat intolerance, exopthalmos and sinus tachycardia likely has what disease
what is the mechanism?
Grave’s disease:
hyperthyroidism is caused by autoantibodies against TSH receptor that activate it
how is Grave’s disease differentiated from Hashimoto’s thyroiditis in terms of symptomology and type of immune reaction
Grave’s causes hyperthyroidism, Hashimoto’s causes hypothyroidism
Graves is type II noncytotoxic hypersensitivity reaction
Hashimoto’s is a type IV cytotoxic hypersensitivity reaction
what are the three P’s of multiple endocrine neoplasia type 1
neoplasias of the parathyroid, pituitary, and pancreas
what’s the range of normal prolactin
normal prolactin < 20ng/mL
which hormone is responsible for regulating plasma sodium concentration with varying salt intake
ADH, not aldosterone
ADH is very sensitive to changes in plasma sodium and responds rapidly to increase water reabsorption in response to increased sodium
aldosterone can only uptake salt and water and in equal amounts so this doesn’t help regulate conc.
what is the thyroid gland like in Hashimoto’s
enlarged and uniformly firm due to chronic inflammation
what antibodies characterize Hashimoto’s thyroiditis
anti-thyroid peroxidase and anti-thyroglobulin
do angiofibromas and lipomas tend to occur more with MEN type 1 or 2
what about pituitary adenomas
angiofibromas and lipomas=type 1
pituitary adenomas=also type 1
a child with short stature, shortened 4th and 5th metacarpals, low serum Ca2+, high serum phosphate and high serum PTH likely has a defect in what molecule
what’s the disease
stimulatory Gs protein PTH receptor leading to failure to raise cAMP in response to PTH
this disease is pseudohypoparathyroidism (defective PTH receptor leading to low Ca)
what are normal levels for serum Ca2+
8.4-10.2 mg/dL
what are Trousseau and Chvostek’s signs and what imbalance do they signify
Trousseau: carpal spasm after application of BP cuff
Chvostek: facial muscle upon tapping in front of the ear
these signs suggest hypocalcemia
activity of which enzyme –that catalyzes the rate limiting step in fatty acid synthesis– is upregulated by insulin
acetyl CoA carboxylase
why might a euthyroid pregnant woman with palpitations, heat intolerance and weight gain have high T4 and normal TSH
- estrogen in pregnancy causes an increase in TBG such that free T4 remains the same, but total serum T4 increases
- TSH is normal because free levels of thyroid influence its secretion, not bound levels
- palpitations and heat intolerance are normal in pregnancy
what are four treatments that would be given to manage a patient with DKA
- insulin therapy
- IV fluids (to manage dehydration)
- dextrose (to prevent hypoglycemia during Tx)
- potassium (to prevent hypokalemia during Tx)
what kind of diabetes monotherapy would you prefer to use in a patient with comorbid kidney disease and heart disease
a second generation sulfonylurea such as glipizide, glyburide or glimeburide
(can’t use metformin due to acidosis toxicity, can’t use glitazones/ thiazolidinediones due to cardiac tox)
the presence of amyloid on FNA suggests what type of thyroid cancer?
what causes this amyloid to accumulate?
what cells proliferate?
medullary thyroid carcinoma;
neuroendocrine parafollicular cells proliferate, leading to build up of the precursor protein to calcitonin which then precipitates and forms amyloid sheets
what are the sites of somatostatin release and what hormones does it inhibit
somatostatin is release from the hypothalamus, pancreas and GI mucosa
somatostatin inhibits GH and TSH
a patient presenting with DKA and peaked T waves on EKG likely has what electrolyte imbalance
hyperkalemia (as well as low bicarb due to acidosis)
up to what size is a lump in the breast of a pubertal boy no cause for concern
pubertal boys often get asymmetric lumps in the breast tissue
up to 4cm in diameter is normal
what does cortisol do to glucose uptake, gluconeogenesis, lipolysis and amino acid levels in blood
cortisol decreases glucose uptake by muscle and adipocytes, increases gluconeogenesis, increases lipolysis and increases circulating amino acid levels
would defective 11-beta-hydroxylase cause decreased or increased deoxycorticosterone
increased 11-deoxycorticosterone because 11-beta hydroxylase convertse deoxycorticosterone to corticosterone
cutting off circulation between hypothalamus and pituitary would cause an increase in which hormone
prolactin:
dopamine from hypothalamus exerts negative regulation of pituitary lactotrophs
would a patient with hyperparathyroidism secondary to end-stage renal disease have high or low Ca;
how would you treat the patient’s hyperparathyroidism
secondary hyperparathyroidism occurs in response to low Ca2+ (due to poor Ca2+ reabsorption in kidneys and calcium phosphate precipitation into urine)
treat with a sensitizer for Ca2+ receptor on parathyroid chief cells to downregulate PTH (i.e. Cinacalcet)
a patient with defective ACTH receptor will have normal levels of what hormone secreted by the adrenal cortex
from what layer is it secreted?
aldosterone: secretion of aldosterone from the zona glomerulosa is unaffected by ACTH action
which class of diabetes drugs are contraindicated in patients with heart failure and how do they work
glitazones/ thiazolidinediones work by sensitizing peripheral tissues to insulin via upregulation of PPAR-gamma activity (increasing adiponectin and decreasing resistin)
a patient with a 2.5cm neckmass and increased serum calcitonin likely has what cancer; what genetic neoplastic syndrome could this patient have
medullary thryroid cancer
(hyperplastic parafollicular cells produce calcitonin)
often seen in MEN2a and 2b (along with pheos)
what happens to PTH in acute vs. chronic hypomagnesemia
in acute hypomagnesemia PTH is increased; in chronic severe hypomagnesemia PTH is decreased
