more about creatinine

[boswife]

ok, here i go again  ..  Today, i asked the dialysis dr if he could order a 24 hour creatinine test for hubby.  Seems he will but......he said that beings his crat is between 4.5-6.1 what would be the reason i want it done as it wont change anything just by  knowing this and he's still going to need dialysis.   Im feeling that i just want to know just how his kidnies are doing not just what the combined efforts (dialysis + kidneys) are doing.  Am i getting this wrong? Obsessive carring??  I really dont want them to say......"oh, he can quit for now" when it's really a good thing even if he is starting early.  (im not saying he is, i just want to KNOW that he is suppose to be doing all this.  Do i have trust issues?? i dont know, i just want the best for him.. 
ps..second day on buttonhole prep :-)




Edited: Fixed Subject Line Error - okarol/admin

[cariad]

It's true that they usually do not order a creatinine clearance for people on dialysis. I sense there is a lot of backstory here that I don't know, as I don't understand why they would say "he can quit for now". Has this been discussed? Those creat numbers are really high. What are they saying his GFR is? Because that is all that the clearance will tell you, and that will fluctuate a little bit with anyone. They can at least give you a GFR range with serum creatinine, what are those numbers?

I guess the most important question that you need to ask is what does your husband wish to do? I have always loathed collecting that urine, so if a doctor told me there was no point, I would be inclined to believe him or her.

[boswife]

thank you cariad,  Im just an over thinker/worrier and i want to KNOW (without a doubt)  that his treatment is spot on.......... Im guessing i need to *trust* that all is done in his best interest.
Hubby is *willing* to do the "test" but it's me that wants it done  ..
But....in my defence, Doesnt the urine test tell just the kidney function,(gfr etc) and the blood one tells the combination of how the kidneys AND the dialysis are working to give the levals? And are they right that at this stage that doesnt really matter as his numbers are still high even with dialysis..
And also, they arn't saying  "he can quit for now" . Thats just something im worried that by me pushing to have certain tests done, they're going to think im trying to get him off D, and grant my wish. 
Anyway, if you got through this mess of mine (geesh you should have seen just a few min ago,, a couple of pages i just deleated..lol) I appreciate it.  I need to go read a book,,,,,,,,,and not one anything about kidneys, heart, diabetes,,,,,,or any health issue..  rest brain!!!

[RichardMEL]

I think there's a bit of a difference here. The creatanine measures the waste products in the blood, and once you're on dialysis it's more or less irrelevant. However the CLEARANCE rate - that's very relevant! That's the rate urea is cleared by the dialysis process - usually measured with a pre-D blood, and post-D blood to measure the change in urea, otherwise known as the Urea Reduction Ratio (URR). The minimum recommended is 65% and reflects how well the dialysis treatment is removing the toxins. This is how hemo sessions (down here, anyway) are measure in terms of clearance. We do it every 3 months. Lately I've been at 75% and I'm very happy with that. PD patients rely more on the Kt/V measure, which is a whole other issue.

The 24 hour urine test.. yeah that's a bit unusual in my book - yeah it will give an indication of GFR and so on. not too certain if it will give a useful clearance measure though? Does your hubby pee much?

[cariad]

Sorry, Richard, I was using clearance as shorthand for creatinine clearance. Yes, I imagine the clearance rate on dialysis is of high importance!

boswife, I doubt they would suggest stopping dialysis just because you are pushing for a few tests. You are trying to be his advocate, and that is wonderful. Keep it up. If you think there is a test he should have and they say no, I say keep checking here or with a trusted medical professional, or wherever you've had good luck with clear information in the past. But in this case, I really do not think it will tell you anything you do not already know. If you want a better sense of how his kidneys are doing without dialysis, try for a blood draw right before he goes on the machine. Theoretically, his creatinine should be at its highest right before treatment.

I hope you were able to distract yourself from all things kidney for a while. We all need to remind ourselves to take these mental breaks, and often!

[boswife]

i tell ya, this heres the best place on earth sometimes :-)  It's increadable to get help from those you trust.  Thanks so much for all the input.  Something else i wonder about  is, Is it normal for people to be in such denial about this diesese?   I tell ya i truly belive that he is healthy as a horse, and they are just making up all this illness....And then the other part of the time im working my self into a frenzie on how to fix him..    Oh well, Were actually doing very well with D and dont even hate it..lol  Were actually probably some of the most upbeat in our unit..  It's just my 'carring' head that gets in the way.

[jeannea]

If he's being considered for transplant or even a referral for transplant they're going to want the results of a 24 hour creatinine clearance. It's an annoyance for the patient but the doctors can find the results useful.

[Bruno]

My doctor made me do a 24 hour urine test every time I did blood tests in the last year of my kidney decline. It used to drive me crazy...it was the one thing I hated most. But I persevered because she said it gave her a more accurate picture of my condition.
As for denial of your kidney condition...what can I say? Everyone does it because the very last thing you want to do is go on dialysis.
I had to apologise (didn't need to, but felt I should) to my nephrologist after I'd been on dialysis a month...I felt so better and realised how stubborn and uncooperative I'd been.

[Riki]

I've never heard of a 24 hour creatnine clearance. What is it?

[AguynamedKim]

As per http://www.nlm.nih.gov/medlineplus/ency/article/003611.htm

The creatinine clearance test compares the level of creatinine in urine with the creatinine level in the blood. (Creatinine is a breakdown product of creatine, which is an important part of muscle.) The test helps provide information on kidney function. 

This test requires both a blood and urine sample. You will collect your urine for 24 hours, and then have blood taken. 

The samples are sent to a laboratory. The laboratory specialist measures the level of creatinine in both the urine and blood samples, and looks at how much urine you collected in 24 hours.

The clearance rate is then calculated. The calculation is adjusted for your specific body size.

The creatinine clearance appears to decrease with age (each decade corresponds to a decrease of about 6.5 ml/min./1.73 m2).

Clearance is often measured as milliliters/minute (ml/min). Normal values are:

•Male: 97 to 137 ml/min.
•Female: 88 to 128 ml/min.

Abnormal results (lower-than-normal creatinine clearance) may indicate:

•Acute tubular necrosis
•Bladder outlet obstruction
•Congestive heart failure
•Dehydration
•Glomerulonephritis
•Renal ischemia (blood deficiency
•Renal outflow obstruction (usually must affect both kidneys to reduce the creatinine clearance)
•ShockShock
•Acute renal failureAcute renal failure
•Chronic renal failure
•End-stage renal disease

[boswife]

thanks aguy ;-)......appreciated!

[RichardMEL]

24 hour urine tests prior to starting D are  normal. I lost count of how many of those bottles I've lugged around over the years before I started. 

My thing is though that once D has commenced, and most people's urine output slows to a trickle or even stops, I wonder at the relevance of these tests. Indeed I've not been asked to do one since I started dialysis - they do URR clearance studies from pre- and post- D labwork and work out how much is leaving then.

I think the difference basically is that pre-dialysis, the 24 hour urine tests measure (more accurately over a period of time) how your kidney is functioning because they need to know how well the remaining function is removing toxins. Once you're on dialysis, it's not so relevant because the machine is taking up that role, and urine output is often decreaed so results of such a test would be less useful, plus they're then interested more in how the dialysis treatments are clearing the wastes, which is why it makes sense to do a pre- and post- labs (I'm talking hemo here, I think PD is way different that you have to give a sample from the cycler or something? I have no experience with PD).

So I guess I'm still a little confused as to why a dialysis patient would need to do a 24 hour urine collection to study clearance.

[cariad]

24 hour urine tests prior to starting D are  normal. I lost count of how many of those bottles I've lugged around over the years before I started. 

My thing is though that once D has commenced, and most people's urine output slows to a trickle or even stops, I wonder at the relevance of these tests. Indeed I've not been asked to do one since I started dialysis - they do URR clearance studies from pre- and post- D labwork and work out how much is leaving then.

I think the difference basically is that pre-dialysis, the 24 hour urine tests measure (more accurately over a period of time) how your kidney is functioning because they need to know how well the remaining function is removing toxins. Once you're on dialysis, it's not so relevant because the machine is taking up that role, and urine output is often decreaed so results of such a test would be less useful, plus they're then interested more in how the dialysis treatments are clearing the wastes, which is why it makes sense to do a pre- and post- labs (I'm talking hemo here, I think PD is way different that you have to give a sample from the cycler or something? I have no experience with PD).

So I guess I'm still a little confused as to why a dialysis patient would need to do a 24 hour urine collection to study clearance.

I agree, Richard. I was told there was no point a year before I began dialysis, even though my urine output always remained quite high. Yes, creatinine clearance is certainly more accurate than serum alone which cannot take into account how much you've had to drink and does not measure the output volume, but really, does it matter if your genuine GFR is 10 or 12? If serum creat were that far off the mark, they would not use it. I did not even have to do a creatinine clearance for my final eval.

[Jie]

The 24 hr urine test does not measure the GFR very well and will always overestimate the GFR when the kidney function is low. That is the major reason that the creatinine/age/race/sex are used to estimate the GFR rather than using the 24 hr urine test. Although the 24 hr urine test may not be conducted very often for HD patients, it is conducted for PD patients every three months in the U.S. (a medicare requirement).

[RichardMEL]

So what if you're on PD and you don't actually output any urine? Are you considered GFR 0?!

[Jie]

This is an interesting question, Richard. Since the eGFR is estimated with creatinine now, so the estimated eGFR could be greater than zero even without any urine output. However, without urine, the residual kidney function is zero. For PD patients, Kt/V consists of two parts: residual kidney function and dialysis. The average of the 24 hr urine test and urine urea clearance is used to estimate the residual kidney function. This seems to be overestimating the residual kidney function too. So, it is very easy to meet the Kt/V target of 2.0 when a PD patient has enough urine. Without urine output, a patient needs a lot of PD to get to Kt/V of 2 or higher.

Come back the question Boswife posted, what he needs is not a simple 24 hr urine test. He needs a test with some injection to accurately measure the residual kidney function or GFR. I guess such a test is not easy since my doctors have never asked me to do such a test. The eGFR formula is deleloped from the results of such tests.

[boswife]

oh wow jie, very interesting!!  Im sort of guessing that im going to let it go and just be happy that his 'results' are good.  Is it possible though (see, here i go with doubts) that his kidneys would actually be doing MOST of  the work and the machine only a little so he could actually wait for further failure before doing dialysis??  That would be not too smart though would it??  if his Creat ON dialysis goes between 4-6 i should just accept that he really needs it right??  Ok, how about this, how do i know what the machine is taking?  is that something that the tech could tell me?  I get feeling like a real pain cause i ask EVERYONE so many questions, but there are always so many more to ask..Every time i think "i got it" i ask something that's really simple that i should have already known   ..

[AguynamedKim]

If you have questions, never stop asking them.  Never be afraid of what people will think, never be afraid of what the answer will be.  Ignorance is the real enemy and it needs to be 

[Jie]

Hi Boswife,

If he is doing PD, nephs do not care about the creatinine levels. What they care are Kt/V, bun and other problems. If he is doing HD, the creatinine levels may not mean much about his kidney functions. The URR described in Richard's post is more meaningful. A very good HD (overnight) can bring a patient's creantinine leve to about 1.5, close to the high end of the normal values. A creatinine bewteen 4-6 on HD does not mean he does not need dialysis. You do ask the right question about his residual kidney function. If he looks very good for everything and does not have any problems, it is not a bad idea to get an evaluation of residual kidney function to decide whether to continue the dialysis. If his neph does not do it, he can ask the primary doctor too.

[Riki]

why would you want to stop dialysis?  I would think, if your kidneys are failing, and you feel like crap, once you've been doing dialysis for a few weeks, you start to feel a heck of a lot better.. that's my experience anyway.. I don't see a point to delaying or stopping dialysis, when it will make you feel better

[boswife]

Thanks again  .. all his labs are great except for his albumin which they say is because of the protien they take out and he cant seem to get enough back in..He eats LOTS of protien, and does the protein shots but still just skims by under the 'good' numbers.  It just seems that it's that give and take and w/o dialysis, he wouldnt have that prob, but w/o dialysis, would he also become ill with the toxins.  Just seems that they should do something to satisfy these doubts.  WE're getting ready for home hemo as well, and mabie the classes will help my 'trust' that this is the right thing to be doing..  I certainly dont want him to get sick because of my desire to make things right.. Geesh, that would just kill me.

hehe,, while i was writing this, i got this next message by Riki     Soooo, i guess that why i would even think of desiring to stoping D would be that hubby always felt good before starting D (well, until he got pumped with a bunch of drugs to do some procedures and couldnt rid himself of them) and each time something like that would happen, he would always bounce back to the pre-diaysis needed stage.. (does that make any sence)  So, i wondered if he did that again and started D prematuraly...  Doesnt sound like it, and i guess yowe're not damaging whats left of his kidneys, so what the heck am i trying to do..  hum

[Zach]

Why not ask your nephrologist for a pre- and post hemodialysis blood chemistry?

That way you'll see what is being removed by dialysis and not his residual kidney function.

[boswife]

YES!!  thank you Zach     he's due for testing on tuesday so hope i can attempt that one then..  gonna have to keep a note on my forhead until then though..lol  I just need to know these things and even if he's borderline needing it (is there such a thing?) i will at least feel satisfied that we're actually lucky to  start early and  save the rest of his body from the effects of bad kidneys..right?!

[Riki]

Boswife, I think I find it hard to understand because I was never given a choice.. I've started dialysis 3 times now, the first being when I was 12, and if they hadn't done it then, I probably would have died.  When my 2 transplants died, I think it was just whenever they could schedule the surgery to have the PD cath put in and they wanted me to start while I was still feeling ok, because it would level off.  If it was left until you were feeling really crappy and was sick all the time, it would take longer to get back to feeling almost normal, so they started earlier than they needed.  There's a reason for everything, even if it doesn't make sense.. it's always best to keep asking questions

[boswife]

Ya know Riki, He really did HAVE to start when he did, but then i just kept encouraging them to check to see if his function returned (because under these same sort of circumstances he always bounced back) and i have never had this answered by them.  I trust his neph (he's highly regarded by all )  and him being from europe where they firmly believe that early is better, i feel like one of the lucky ones...........on one hand that is. On the other, hubby always feels good, before treatment, and almost always after as well so he's he's not one that has gotton to *feel* the benifits of dialysis..  We shall see.  And learn