I was once told that my eGFR was not accurate cause I am small (4'9", 92 lbs) and at the time training for and competing in 50ls. I no longer train or compete due to fatigue but I'm still small. If eGFR using the creatinine from blood work is inaccurate why do doctors not use the Creatine Clearance calculator (mdcalc.com/creatinine-clear.... It takes into account age, sex, height, weight and creatinine to come up with the GFR.
If I use the normal formula my eGFR is 22; with the Cockcroft one my eGFR is 17. I see my nephrologist on June 7 and intend to bring this up as it affects whether or not I can get a referral to the transplant center and/or start the process for PD.
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horsie63
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Our egfr as it states is an estimate not an absolute there is not much of difference although I know it is always nice to see a higher number but it is better to watch for symptoms of uremia and try to do anything that promotes heart health. also our egfr fluctuates throughout the day so it may be 15 at one point and 25 etc If you are on transplant list then egfr is the least of your worry right now. You need a strong heart for the transplant. So don't give yourself too much stress it is bad for kidneys. However do let your Dr know your concern they are your best source of advise because we don't know your health. Take care.
Thank you. I do have high BP which is now treated and under control. And I have Graves Disease an autoimmune disease that causes hyperthyroidism but it's in remission and to keep it there i do need to watch my stress level. I do not have diabetes and am not overweight. I used to be quite athletic but am so tired most days I haven't really done much but I do hope to at least begin walking again.
The Cystine C test is the most accurate, and the reason it is not done on the regular is that it is more expensive than the creatine test. Nevertheless, those numbers are just estimates. They could be plus or minus 10 pts any given day. That is why tracking/trends are used instead.
I was talking about the Cockcroft formula which doesn't use race in the calculation. It's based on age, sex, height and weight which I would think for someone like me (on the small side) would be a little more accurate and not racist. I understand they are nothing but estimates and other factors can play into each test.
Being muscular myself---I don't feel that a test that provides the best estimates based on muscularity is racist. Nevertheless, the Cystatin C is the most accurate regardless of muscle mass or how you might feel
Horsie63. there are over 7 0 calculation for eGFR. EGFR itself is not intended as a one result diagnostic of kidney damage it is too inaccurate to be used as that type of tool. Rather it should be used as a series of lab results every 3 or 6 months to track kidney function/damage to be sure one the underlying condition is treated it stabilizes. EGFR is in list of us as much as 30/50% inaccurate regards mGFR. Why? Because it is an estimate using creatinine which is more unreliable than eGFR. Creatinine can be affected by multiple inputs (food or drink) or exercise or the rain in Spain (lol). Agencies such as the NKF, ASN and NIDDK in the US in their practice recommendations to physicians and labs recommend that eGFR NOT be reported as a whole number to patients or doctors…why? Because it becomes an obsession of both that leads to post such as we have a whole group of “let me share how I cured my CKD using plant based and Lee Hulls $500 probiotics” or “ why do the say CKD can’t be reversed I know a group of 6 people who went from stage 3 to none” and as we both know that is bunk.
EGFR is measuring kidney damage . If you are stage 4 with eGFR 80% lower than normal that effectively means you have destroyed 80% of the special blood filtering kidney cells called nephrons. Unlike liver or kidney cells those do not regenerate. Once they are gone they are gone and then if your gave protein leaking more are being destroyed. If you are stage 4 since CKD is progressive more are destroyed. So because of the inaccuracies and the fact that eGFR only tells you a small part of how your kidneys are functioning as well as the fact that there are over 70 ways to calculate eGFR, I wouldn’t worry about one reading. My eGFR from 12/2020 has been 17, 22, 24, 27, and 29. That is about an 80% variation from low to high. Am I worse better then worse? Absolutely not. It is the nature of the way eGFR works and the way it’s calculated. Finally the NKF, ASN and NIDDK along with counterparts across the world changed the recommended calculation to eliminate race. That gave most of us a boost of 5 points or so. That correlates to my 29 reading,
EGFR is more accurate generally using Cystine C but that has additional problems. The calculation you are using is the new official recommended without race. So you are spot on and it is about 5 points higher as I mentioned.
The reasons this is used as opposed is something I have always been wondered about as well. Primarily because it is easy for labs to calculated and report back quickly. For decisions like you mentioned in your OP, to decide dialysis after eGFR sub 15 it is not considered much more in the decision to start dialysis. It s a switch back to creatinine and BUN as they become more important again along with any additional abnormalities specific to you like anemia or potassium. I know many folks who are eGFR sub 10 and have no plans to start dialysis due to the many other more important factors used to make that decision. Finally, you have a really good plan to as your nephrologist about the eGFR provided you are fairly confident he/she will know or be willing to look up. As you know many doctors including nephrologist don’t know and I have read studies recently that as many as 59.7% of them do not use the ASN or NKF guidelines at all in their practice. It’s what they learned in med school or picked up anecdotally from partners or professional conferences. The most recent guidelines that include the recommended change in eGFR calculation last year are from 2021. In the last 5/6 years with the commitment of the US government and the agencies I mentioned information is changing rapidly and innovation is coming fast so you want your nephrologist to be plugged in. Not saying they are not but just fyi. I hope some of that might help and I hope I didn’t offend by offering info you already knew. Just like you my initial CKD diagnosis in February 1996 of stage 4 was due to HBP which the Army knew about prior to my admission to West Point, but I didn’t know about till February 1996 and and the Army’s love of prescribing 120 800mg ibuprofen for sprains and strains to help us keep going. Of course, 4 days later due to a mistake made by a Iranian ER doctor who graduated from the med school in Granada I had AKI with multi-organ failure and sepsis. 4 months on a ventilator and 6 months in the ICU. So it was always until 2020 for me creatinine and BUN that was tracked I didn’t even know about eGFR until 2020 for me. I wish you the very best and I’d be interested in your nephrologist reply if willing to share. I see mine in a couple of week and plan the same so I’ll share back if you’d like. My guy is top notch a member of ASN and a fan of keeping up with all the exciting new type of treatments and recommendations coming out that will help him keep his patients from the life changing end options of dialysis only for me since I have too many comorbities for transplant. Let me know and take care!
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Louisa question
Why are eGFR calculations different?
Concerned about kidney function numbers going down
MY CKD JOURNEY..FROM EGFR OF 11 TO EGFR OF 84.. FROM AKI 5 TO CKD 2.. STRUGGLING WITH LOW SODIUM LEVELS.
creatinine levels
