For all of us who have gotten a little anxious over a drop in GFR or a raise in Creatinine or Albumin from one test to the next, maybe this will ease your mind, or perhaps make you go "hmmm" like it did me. I went to the lab this week and had blood work done by 3 different doctors as we are trying to unravel some mysterious symptoms. In any case, my nephrologist and my neurologist requested some of the same tests. Not sure why as my neurologist knew I was getting tested again, but in any case they did. I had something like 12 vials drawn.
So, I get the results from the nephrologist back first and yeah! my GFR rose by 9 points since the last time when it had dropped by 5. My protein leak also decreased by 100 as it had risen last test. I was thrilled. Then, several days later, I got back my nephrologist results of the same things, GFR, creatinine, albumine, BUN, etc. They were about 4 points worse than the first test. Still happy with the results, but WHAT Is going on? They were drawn within 10 minutes of eachother at the same sitting, however my veins dried up and they had to switch arms. They said that could have been a factor. They said they allow a 5 point difference. When I questioned them about how much they allow on smaller point difference items like Creatinine, they only said that different machines analyzed it and that my differences fell within an acceptable allowable error.
So, there you go! Conclude what you'd like.