We have compared the estimated creatinine clearance with the newer methods of the calculations of eGFR with the use of the concentration of creatinine, cystatin C and/or their combination in 352 patients with chronic renal disease (174 men, 178 women), mean age 54 years (41-66). Patients on chronic dialysis programme were not included.
Median of the values of creatinine clearance was 1.21 ml/s/1,73 m2. Al the methods for the calculation of eGFR gave significantly lower values - 1.01 ml/s/1,73 m2 for creatinine, 0.93 ml/s/1,73 m2 for cystatin C, and 0.96 ml/s/1,73 m2 for the combination of creatinine and cystatin C.
The "classical" calculation of glomerular filtration based on creatinine clearance is significantly less sensitive that any of the eGFR calculation.