ABSTRACT

Conventionally, renal dysfunction is detected by impairment of glomerular filtration rate, reflected by elevation of the plasma creatinine (cr) or diminution of the creatinine clearance, and/or proteinuria. The heterogeneous nature of the kidney and of the mode of drug toxicity necessitates the use of several tests specific for different aspects of renal integrity. Urine is a readily accessible fluid but a highly variable and relatively hostile environment. Analytes and their assay methods must be sufficiently robust to withstand the range of urine pH, ionic strength and composition, proteolytic enzymes and contaminating bacteria without elaborate patient preparation or urine collection conditions. Drug-induced nephrotoxicity occurs via numerous mechanisms and may develop acutely or chronically. Sensitive tests to detect subclinical abnormalities may be useful to determine the inherent toxicity of a drug; to compare the relative toxicity of different drugs with a similar therapeutic index; and to select and monitor patients for Phase II trials to minimise the risk of toxicity.