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Old 04-29-2011
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Kidney renal failure , level of ca, phosphate

in renal failure what is level of calcium and phosphate
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Old 04-29-2011
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From my understanding...if you are in renal failure...you can not make 1 alpha hydroxlase (the enzyme that converts vitamin D into the active form)...there for you can not reabsorb Calcium. So calcium levels will be low, PTH will be high since PTH is working fine i.e secondary hyperparathyroidism.

As for Phosphate. Phosphate will be increased since the kidneys can not excrete Phosphate.

The main cause of CHRONIC renal failure is relating to secondary hyperparathyroidism.

So Increased PTH, no 1 alpha hydroxylase to convert Vitamin D to the active form (1,25) which would reabsorb calcium, so therefore low calcium, and since there is renal failure, therefore no excretion of phosphate, which would increase phosphate levels.

Hope this is correct and it helped!!
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Old 04-29-2011
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Its easy to understand my friend...

Kidney are Failure... so they dont Respond to PTH.. so here's what you got

* PTH Increase Because it wants to Increate CA, but kidney is not responding so CA lvls stays down and PTH thinks that it his problem so it goes UP.

* Ca Lvls are Decrease Because Kidney is not responding to PTH, so there is not way to reabsorp CA over the proximal tubule neither over the Intestine becaue there is not production or better say "Conversation" of 25 hydroxilase to 1,25 hydroxilase.

* Phosphate should be DOWN but Kidney is not responding to PTH so it wont Trash the Phostate. so Phosphate is INCREASE.

* You will not get any lvl of Alkaline phosphate.

Hope this help you understand...
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Old 04-29-2011
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Quote:
Originally Posted by rulz View Post
Its easy to understand my friend...

Kidney are Failure... so they dont Respond to PTH.. so here's what you got

* PTH Increase Because it wants to Increate CA, but kidney is not responding so CA lvls stays down and PTH thinks that it his problem so it goes UP.

* Ca Lvls are Decrease Because Kidney is not responding to PTH, so there is not way to reabsorp CA over the proximal tubule neither over the Intestine becaue there is not production or better say "Conversation" of 25 hydroxilase to 1,25 hydroxilase.

* Phosphate should be DOWN but Kidney is not responding to PTH so it wont Trash the Phostate. so Phosphate is INCREASE.

* You will not get any lvl of Alkaline phosphate.

Hope this help you understand...
Hey guys, I think a very important point that was missed here was the role of phosphate on calcium levels. You are both right about what you said, but with the increased PTH, one might expect that calcium is compensated for because more is being released from bone (where >99% of our Ca is stored)

A key concept to understand is that phosphate levels rise due to decreased GFR. This phosphate will then bind ionized calcium in the blood, thus diminishing calcium levels (ionized calcium is functional calcium). PTH is trying to compensate for the Calcium loss by the kidney, but when Ca is released from the bone, Phosphate plucks it out of the circulation. Thus PTH remains high, calcium is low, and phosphate is high. The increased Calcium Phosphate can actually deposit in tissues with an acidic environment even though calcium levels are low!

Hope that makes sense/helps.
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