Acute Kidney Injury and Renal Recovery with the Use of Aminoglycosides: A Large Retrospective Study.

BACKGROUND Recent acute kidney injury (AKI) guidelines, based on studies performed a decade ago, recommend avoiding aminoglycosides (AGs) in patients at risk of AKI. Whether present patient characteristics and management have changed this risk is uncertain. We determined the current incidence, risk factors and outcomes of AG-AKI. METHODS We retrospectively identified adult patients who received gentamicin or tobramycin for ≥5 days in 2 large university-affiliated centers, excluding critically ill and dialysis patients. We assessed the incidence of Risk, Injury, Failure, Loss and End-stage kidney disease criteria of AKI risk and then matched each AKI to 2 controls of same age and gender to determine factors associated with AG-AKI and its recovery, defined by a creatinine within 150% of baseline by 21 days. RESULTS Since 2001, the frequency of AG administration and dosing declined, but the incidence of AG-AKI remained constant. Of the 562 patients who received AG for ≥5 days, 65 (12%) developed AG-AKI after 11 (IQR 8-15) days, with 56, 29 and 15% having stages 1, 2 and 3 AKI, respectively. We matched these to 130 controls. In this nested case-control study, independent AKI risk factors were vancomycin coadministration, high AG trough levels and heart failure. AG-AKI compared to AG exposure without AKI was associated with greater mortality. Renal recovery occurred in 51% of the AKI patients and was less likely with heart failure and higher AKI severity. CONCLUSION AG administration has recently decreased but the risk of AKI remained unchanged and half of the patients did not recover. Vancomycin coadministration, high AG trough levels and heart failure independently predicted AKI.