Discussion
It is well known that all four considered methods do detect kidney damage induced in rats by high gentamicin doses far above doses used in clinics. The present investigation shows that only the analysis of the urinary phospholipids will detect damage induced by low doses of gentamicin. The method is relevant for animal model studies but will require considerable and innovative development for use in clinics.
Methods
We have therefore compared the sensitivity of four methods currently used in animal models to assess kidney injury induced by aminoglycoside antibiotics by applying them to the analysis of urine from male rats treated with low doses of gentamicin.
Results
Excretion of phospholipids was significantly increased in contrast to excretion of N-acetyl-beta-glucosaminidase (NAG), neutrophil gelatinase-associated lipocalin (NGAL) and protein. Assessment of phospholipiduria thus is the more sensitive noninvasive way to monitor initial renal injury induced by aminoglycoside antibiotics. A protocol is given for the serial analysis of urinary phospholipids allowing a considerable number of determinations to be carried out in the course of 2-3 days.