The measurement of renal injury.

The classical assessment of nephrotoxicity by the measurement of serum urea nitrogen and creatine is insensitive and nonspecific. Selection from a battery of clinical pathology tests allows the sensitive and specific measurement of renal dysfunction and injury. This requires the collection of urine specimens of good technical quality, with appropriate preservation. Interaction of the test article with urinary enzymes should be evaluated prior to their measurement for the assessment of tubular injury. This enables the localization and quantification of the injury within the regions of the nephron. High resolution proton nuclear magnetic resonance spectroscopy, a technique for measurement of low molecular weight metabolites, shows great promise for the evaluation of renal tubular injury in toxicologic studies.