Correlation of renogram with cystatin-c levels and creatinine clearance in measuring glomerular filtration rate

Renogram using 99mTc-DTPA (diethylenetriamine pentacetic acid) has advantages in the measurement of glomerular filtration rate (GFR). Serum cystatin-c was recently projected to be the new marker of estimated GFR. The aim of this study is to establish correlation between GFRs, derived from renogram with cystatin-c levels and creatinine clearances in chronic kidney disease patients.We put to study thirty consecutive stage two of chronic kidney disease patients assigned based on GFR estimation by Cockroft-Gault’s formula, taking into account the serum creatinine. Cystatin-c and creatinine clearance were performed to determine of GFR and renogram was included in this study. A total of thirty subjects, the mean of GFRs were taken from renogram, cystatin-c, creatinine clearance, Cockroft-Gault’s formula were 64.96 ml/min/1.73m2 (SD 28.047), 53.37 ml/min/1.73m2 (SD 21.29), 58.09 ml/min/1.73m2 (SD 35.45), 46.00 ml/min/1.73m2 (SD 12.06) respectively. A correlation between renogram with cystatin-c (r = 0.585 and p = 0.0007) and renogram with creatinine clearance (r = 0.388 and p = 0.03) and renogram with Cockroft-Gault’s formula (r = -0.029 and p=0.87). This study has shown that a better correlation between renogram with cystatin-c than with creatinine clearance or Cockroft-Gault’s formula. Furthermore, cystain-c would be better alternative method incase having problems to obtain a closest ideal methods for GFR.