Gentamicin gradient patterns and morphological changes in human kidneys.

The gentamicin gradient pattern was studied in ten autopsied patients who expired during gentamicin therapy. Although two of the patients had acute renal failure, none was thought to have gentamicin-related nephrotoxicity. Gentamicin concentrations in cortex significantly exceeded those in medulla or serum (p less than 0.05 and p less than 0.01, respectively). No correlation was found between the cortical concentrations and the total drug dose, the time interval between the last injection and death, or the plasma creatinine concentrations in this heterogeneous group of patients. In addition, two specimens were suitable for electron microscopy which displayed cytosegrosomes and myeloid bodies previously noted in experimental animals. We conclude that gentamicin forms a gradient pattern in human kidney similar to that described in experimental animals. Furthermore, it evokes similar morphological changes.