@sharlea1313 In my opinion, there is a difference between cautionary and insignificant. eGFR quite often jumps between values from day to day and perhaps within a day and among various labs. Cystatin C eGFR perhaps is more stable. A score of 53 out of normal 60 is still a good value so I agree with your doc, that at this point it is of no concern, but cautionary. eGFR works only with trends so if you are concerned, have the test repeated in 2 or 3 months. The "e" in eGFR means "estimated", so it is nothing more than that. The only true tests for kidney function are the iothalamate and/or iohexol, and you are nowhere near that. Stages 1, 2, and 3a are cautionary, easily handled by your PCP with repeat testing, and a referral to a nephrologist if your PCP deems nevessary.