Clinical significance of renal changes engendered by aminoglycosides in man

Aminoglycoside antibiotics are associated with decreasing renal function of sufficient magnitude to influence adversely the management of approximately 10% of cases. Onset usually occurs after one week's treatment, but may be delayed until after the drugs are discontinued. Renal insufficiency is generally transient, mild, non-oliguric, and is characterized by recovery. There is currently no clear evidence that aminoglycosides cause permanent or subsequent progressive renal damage. Although age, pre-existing renal dysfunction, volume depletion, prior exposure to other nephrotoxic drugs and total drug dose have been suggested as host variables on the basis of animal studies, human studies have not shown predictive factors of toxicity. Peak and valley serum concentrations are more likely to reflect renal function than to predict toxicity. Studies in man are dogged by confounding variables characteristic of the critically ill. Comparative trials of toxicity have required the enrolment of large numbers of patients to show statistical differences which may have little clinical significance. Thus the choice of aminoglycoside should not be governed by nephrological criteria.