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DrVirgo
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03/27/07 - 07:21 PM       #1

In chronic renal failure, what are the levels of Ca? PTH? and Phosphate?

Renal failure---> Decreased Ca (cant be reab.)
so Increased PTH (right?)

And PO4?

Will it be increased due to the decreased GFR from renal failure?
OR will it be decreased due to the increased PTH???

??????




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mytime
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03/27/07 - 07:25 PM       #2

hypo Both hypo.







sprint123
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03/27/07 - 07:27 PM       #3

CRF-->Decreased Vit-D--->Decreased Calcium--->Secondary Hyper-Parathyroidism--->However,The increased po4 excretion action of PTH does not occur due to inability of the kidney to excrete po4.

So,Lab will look like increased po4 and decreased Calcium.

CRF is the only cause of secondary hyper-parathyroidism with opposite levels of po4 and calcium.In all other causes-it is both decreeased calcium and po4.

Hope this helps..Please do correct me if I am wrong

new_n_lost
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03/27/07 - 07:38 PM       #4

My 2 Cents.

Phosphate Retention Occurs very early in the Disease which doesnt lead to High Serum due to Inc. Serum PTH which leads to Phosphate excretion. But later on as the GFR decs the Renal Excretion of Phospate decs.

Hyperphosphatemia suppresses the renal hydroxylation of inactive 25-hydroxyvitamin D to calcitriol, so serum calcitriol levels are low when the GFR is less than 30 mL/min. Hypocalcemia develops primarily from dec. intestinal calcium absorption because of low plasma calcitriol levels and possibly from calcium binding to elevated serum levels of phosphate.If serum levels of PTH remain elevated, osteitis fibrosa develops.

Other Findings Include: Hyperkalemia, low serum bicarbonate, hypocalcemia, hyperphosphatemia, hyponatremia (in ESRD with free-water excess)




Edited by new_n_lost on 03/27/07 - 08:18 PM

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Luckyall
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03/27/07 - 08:12 PM       #5

yeap, hypo Ca-emia & hyper Ph-emia

mytime
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03/27/07 - 09:23 PM       #6

YO my bad was more worried about getting the smiley right.....Check ur pm though DRVIRGO.







DrVirgo
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03/28/07 - 03:51 PM       #7

Ok, so we are all in agreement: CRF causes HYPOCalcemia and HYPERPO4??

Thanks mytime.... got the pm.


and, cute smileys. smiling face

Luckyall wrote:
yeap, hypo Ca-emia & hyper Ph-emia



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