Glomerular filtration rate (GFR) is the most important parameter of renal function assessed in renal transplant recipients. Although inulin clearance is regarded as the gold standard measure of GFR, its use in clinical practice is limited. Krieser et al. (A-6) examined the relationship between the inverse of Cystatin C (a cationic basic protein measured in mg/L) and inulin GFR as measured by technetium radionuclide labeled diethylenetriamine penta-acetic acid) (DTPA GFR) clearance (ml/min/1.73 m2

).

The results of 27 tests are shown in the following table. Use DTPA GFR as the predictor of inverse Cystatin C.

DTPA GFR 1/Cystatin C DTPA GFR 1/Cystatin C 18 0.213 42 0.485 21 0.265 42 0.427 21 0.446 43 0.562 23 0.203 43 0.463 27 0.369 48 0.549 27 0.568 48 0.538 30 0.382 51 0.571 32 0.383 55 0.546 32 0.274 58 0.402 32 0.424 60 0.592 36 0.308 62 0.541 37 0.498 67 0.568 41 0.398 68 0.800 88 0.667