Assessment of Nephrotoxicity by Analysis of a Randomized Multi-Centre Comparative Study Regarding the Previous Extend of Kidney Damage

Abstract

For the assessment of nephrotoxicity we need to differentiate between kidney alteration, kidney lesion and kidney necrosis. Any toxic agent may first alter kidney structures by means of reversible effects on kidney cells without cellular destruction and no functional impairment. More toxic agents may then lead to lesions of kidney structures by means of cellular destruction with compensate functional for the impairment of the kidney. Toxic agents leading subsequently to kidney necrosis show cellular destruction and not compensated functional impairment of the kidney damage (Table 1). The main parameters of nephrotoxicity in clinical use, such as creatinine in serum, creatinine-clearance and protein in urine are functional parameters shown to be sensitive for kidney necrosis, poorly sensitive for kidney lesions and not sensitive for kidney alteration. Concerning kidney damage they have therefore to be evaluated as late phase parameters. Every drug related nephrotoxicity begins with alteration of the kidney before leading subsequently to lesions and necrosis. It is of importance to detect nephrotoxicity in their early stages of alteration before cell destruction and consequently functional impairment occurs.