ESTIMATION OF CREATININE CLEARANCE WITHOUT 24-HOUR URINE COLLECTION -A USEFUL GUIDE DURING CISPLATIN THERAPY

The validity of the Cockroft and Gault formula in monitoring renal fun ction during cisplatin therapy was examined in 110 consecutive cancer patients. A good correlation between estimated creatinine clearance (E CC) and the standard measured creatinine clearance (MCC) was found bot h before and after the onset of cisplatin. The correlation was better in males (r = 0.78 prior to cisplatin and r = 0.79 after the initiatio n of cisplatin) than in females (r = 0.69 and r = 0.63 respectively). Obesity ( > 125% of ideal body weight) had no major effect on the corr elation between ECC and MCC. The presence of third-space body fluids, on the other hand, had an influence on the relations between ECC and M CC, particularly in females (r = 0.49). It is concluded that estimatio n of creatinine clearance, without the cumbersome collection of 24-h u rine specimens, is accurate enough for the purpose of adjusting cispla tin dose. It should not be used in females with third-space body fluid s.