[Acute change in urinary NAG activity following CDDP administration]

In the present paper, the acute change of urinary NAG activities following CDDP administration was studied in 8 patients with urological malignant tumors. The activities were measured for 11 days from the day before CDDP administration and were expressed as U/day. According to the NAG activity and creatinine clearance (CCr), the patients were divided into 4 types. In type I (normal NAG activity and normal CCr), the increase of the NAG activity following CDDP administration was transient. In type II (normal NAG activity and low CCr), the NAG activity increased and decreased as in type I, but in type II, the NAG activity rebounded a few days after the completion of CDDP administration. In type III (high NAG activity and normal CCr) and in type IV (high NAG activity and low CCr), the increase of the NAG activities continued longer than in type I, II; especially in type IV, the increase and the prolongation of the NAG activity was prominent. The timing of CDDP administration is considered important to avoid renal toxicity of CDDP.