Boards and Beyond Deck for things I didn't know Flashcards
PTH acts on the kidney to increase ca resorption where?
what about for lowering phosphate?
DCT
PCT
What does PTH do on the kidney Proximal tubule?
we know that it lowers phosphate. it does this by inhibiting Na/PO4 transporter on the luminal side so it’ll stay there and be excreted
PTHrP?
produced by many tissues but synthesized in large amounts by some tumors.
leads to hypercalcemia in malignancy because it does the same thing as PTHrP
Hyperparathyroidism
Primary (overactive glands)
secondary (overactive due ot persistent hypocalcemia)
Primary hyperparathyroidism?
inappropriate PTH, not due to low calcium.. due to autonomous release from the parathyroid glands!
parathyroid adenoma
excess PTH means hypercalcemia
high PTH, high Ca
urinary calcium level in primary hyperparathyroidism?
urinary calcium level in primary hyperparathyroidism should be high.
high PTH causes urinary reabsorption through high serum Ca.
hypercalcemia leads to more calcium being filtered, which leads to more urinary calcium.
symptoms of hyperparathyroidism?
Stones (kidney stones), Bones (bone resorption), Groans (constipation), Psychiatric overtones
Secondary Hyperparathyroidism?
path and ca levels?
occurs in renal failure
chronically low serum calcium –>
leads to chronic elevation in PTH.
this is a normal response but if it chronically elevated it’ll screw with the bones.
HIGH PTH, LOW CA
why is there chronically low serum calcium?
sick kidney have elevated phosphate, and they can’t activate vitamin d so you have low forms.
high phosphate will bind with ca and pull it from the calcium lowering the calcium levels
low active vitamin d will prevent calcium from going back into circulation from the gut so you have hypocalcemia
Familial Hypocalciuric Hypercalcemia?
urinary calcium?
serum calcium?
PTH?
abnormal CaSRs
found in the parathyroid and kidneys
higher than normal set point for calcium, so you could have a higher than normal or normal PTH level but the calcium is super high
because the CASR is found in the kidneys, there’s more renal resorption of calcium,, hence low urinary calcium hence “hypocalciuric”
low
elevated
normal
Difference between FHH and primary hyperparathyroidism?
FHH you’ll have low urinary calcium
Primary you’ll have high urinary calcium
Hypoparathyroidism?
symptoms?
inappropriately low PTH
low PTH
low Ca
causes hypocalcemia like symptoms
Trousseau’s sign
Chvostek’s sign
use when doing what?
hand spasms with BP cuff inflation
facial contraction when tapping on nerve next to ear.
hypocalcemia
Classic example of hypoparathyroidism?
patient comes in after post op with tingling and spasms.. check for calcium, it could be a parathyroid cut.
Pseudohypoparathyroidism?
kidneys and bones unresponsive to PTH
abnormal PTH receptor
impaired Gs signaling!
High PTH APPROPRIATE
low Ca
