7.31 A Parathyroid Flashcards
(25 cards)
3 organs that PTH affects (and what are the effects)
1) bone
- stimulate osteoclasts
2) kidneys
- reabsorb calcium
- excrete phosphate
- activate vitamin D
3) intestine
- absorb calcium
secondary hyperparathyroidism due to
chronic renal insufficiency (can’t convert vit D to active form and can’t excrete phosphate)
familial syndromes that cause hyperparathyroidism
MEN1
MEN2A
familial hypocalciuric hypercalcemia (abn PTH receptors in parathyroid and kidney)
solitary, well circumscribed mass of chief cells and no fat separated from normal gland by thin capsule
parathyroid adenoma
all four glands are small with predominating chief cells
primary parathyroid hyperplasia
can only diagnose parathyroid carcinoma if
locally invasive or mets
patient with no complaints, but has high serum calcium
asymptomatic hyperparathyroidism
bones hurt, had a kidney stone, stomach hurts with constipation, feel depressed
symptomatic hyperparathyroidism
bone cortex thinned
fibrotic marrow with hemorrhage and cysts
osteitis fibrosa cystica
aggregates of osteoclasts, giant cells, hemorrhagic debris in bone
brown tumors of hyperparathyroidism
hyperparathyroidism involves increased activity of
osteoclasts
lab in primary hyperparathyroidism
high PTH
high calcium
low phosphate
high urine calcium and phosphate
high urine cAMP
mechanism of chronic renal insufficiency
don’t excrete phosphate, so increase phosphate
decrease serum calcium
increase PTH because of low calcium
high PTH
high calcium
low phosphate
primary hyperparathyroidism
high PTH
low calcium
high PTH
secondary hyperparathyroidism
treatment for tertiary hyperparathyroidism
parathyroidectomy
if symptomatic hypercalcemia, most common cause is
malignancy
if asymptomatic hypercalcemia, most common cause is
primary hyperparathyroidism
bone cancers secrete what hormone
PTHrP
low PTH
low calcium
hypoparathyroidism
most common causes of hypoparathyroidism
mistakenly removed all parathyroid during thyroidectomy
autoimmune diseases (APS1)
patient with mouth numbness, tingling of fingers and toes, spasm of hands and feet, laryngeal spasms, convulsions
hypoparathyroidism
tapping along course of facial nerve causes contractions of muscles of eye, mouth, nose
- called what
- dx
Chvostek sign
hypocalcemia from hypoparathyroidism
blood pressure cuff causes hand spasms
- called what
- dx
Trousseau sign
hypocalcemia from hypoparathyroidism
