G. Paulus

Early Toxic Events in Kidney of Rat and Man Following Administration of Gentamicin at Low Doses

Kidney cortex of rats and humans treated with low doses of Gentamicin have been examined both morphologically and biochemically. Specific alterations of the lysosomes (loss of activity of phospholipases; accumulation of phospholipid-like material) was detected as early as from 2-4 days of treatment. This finding is consistent with the concept that Gentamicin exerts its toxic action on kidney through lysosomal dysfunction.

Lysosomal modifications in human proximal tubule induced by aminoglycoside treatment: visualisation by light microscopical cytochemistry.

In cryostat sections of kidney biopsies, lysosomes were visualized for light microscopy by staining for acid phosphatase. Twenty patients treated with the antibiotics gentamycin, tobramycin, amikacin or netelmicin during four days were compared to ten untreated control biopsies. Because of the marked heterogeneity of enzyme reaction product through the nephron, the most strongly stained tubular sections were used for comparison. With the exception of one biopsy, all treated kidneys display heavier staining than all controls; the difference is significant. Biochemical assays of acid phosphatase activity in homogenates have not revealed this difference. The cytochemical method may be used to detect early alterations caused by nephrotoxic drugs.