Folks, ESPECIALLY you folks in the earlier stages of CKD, please do yourselves a favor and learn about Cystatin C (pronounced siss-tay-tun C). It is a protein in your system that is used as an alternative biomarker to determine kidney function, and the likelihood of deterioration to both end stage renal and heart disease. ALL nephrologists acknowledge Cystatin C as potentially a game changer in helping to diagnosis and stage kidney disease. Fringe progressive nephrologists will use it as the ONLY test to determine kidney status, whilst the most conservative old time nephrologists might brush it off entirely. More and more mainstream nephrologists are using it as an adjunct to their diagnosis and treatment plan. I was diagnosed two years ago with borderline Stage 2-3a and my nephrologist hadn't ordered a Cystatin C test, so for the past 2 years as my eGFR has danced between >60 and 52, my mind has gone in and out of a tailspin with worry. That's just who I am....I'm a natural born worrier. Of course, Stage 3a is completely brushed off by most nephrologists (if can even get to SEE a nephrologist at that stage), but it sure is hard to brush it off by us patients.
So I just got my most recent bloodwork back and my eGFR was at 56, up from 52 six months ago. When I was first diagnosed, it was 59, then >60, then 58, then 52, blah blah blah. So what did I do? I cut back on red meat, brought my protein down to 50-60 grams per day....AND STARTED EXERCISING, DRINKING LOTS OF WATER...2-3 ltrs/day, and started eating more fruits and veggies. I feel better, look better, and my GFR went up slightly. After buying Lee Hull's book, I'm considering moving towards a more vegetarian/vegan diet in order to reduce the acid load on my kidneys.
OK, back to Cystatin C....
GET....THE....TEST....DONE !!!
In my case, my GFR was recalculated up to 85. WOW!
My regular creatine-only based GFR is 56.
The combined equation gives me a GFR of 70. I'll TAKE IT!!!!
Most importantly, the Cystatin C test, when used in conjunction with the creatinine test, tells you the likelihood of your CKD worsening...unless you're already at low Stage 4 or 5, of course. Here's the takeaway; If your Cystatin C calculated GFR is ABOVE your creatine GFR, that's AWESOME news and heightens your prognosis significantly. The greater the difference, the better your prognosis. Mine was nearly 30 pts better and all my lab work confirms that everything else is normal, although I haven't received my results back from my 24 hour urine collection yet. ON THE FLIP SIDE, if your Cystatin C GFR is at or below your creatine GFR, it portends a worse prognosis.
Again, all this Cystatin C stuff is a little bit controversial. Some of the top nephrologists want to do away completely with the creatinine formula and replace it Cystatin C so that fewer folks are diagnosed with CKD. Most nephrologists are taking a wait and see attitude. Many are acknowledging its potential importance and using it in their overall assessment when discussing with patients. Bottom line: Make your pcp or nephrologist order the test. It took a little pushing from me, but they did it, and now I feel much better because my prognosis for end stage renal disease and heart disease is much better.
Once you get the test result, feel free to plug into this calculator. I hope your result is as positive as mine was.
kidney.org/professionals/kd...
Keep drinking!
If I recall corrrectly, the only thing that can throw of the cystatin c number is if you have thyroid problems.
Serum or urine test results for CKD?
Just going into CKD stage 5 and need your advice please
Referred by GP but renal team won't see me
Positive results after five months
