Is There a Significant Difference in Acute Kidney Injury Incidence Among Patients Treated with Vancomycin Combined with Cefepime or Meropenem?

BACKGROUND: Acute kidney injuries (AKIs) are common among patients receiving concomitant vancomycin (VAN) and piperacillin-tazobactam, especially compared with cefepime (FEP) with vancomycin. It is unknown if there is a significant difference between therapeutic alternatives to piperacillin-tazobactam. We hypothesized that AKI rates would be similar in patients treated with FEP+VAN and meropenem (MEM)+VAN. METHODS: Demographic and clinical data were abstracted from the University of Kentucky Center for Clinical and Translational Sciences Enterprise Data Trust from 2008 through 2015. Patients were included if they received VAN and FEP or MEM in combination for ≥48 hours. Patients with baseline CKD and creatinine clearance <30 mL/minute were excluded. AKI was defined as meeting any of the Risk, Injury, Failure, Loss, End-stage (RIFLE) criteria. Basic descriptive statistics were performed in addition to bivariable and multivariable logistic regression for AKI. RESULTS: In total, 3662 patients were included in this study with 3366 patients receiving FEP+VAN and 296 receiving MEM+VAN. Demographic characteristics were evenly distributed among both groups, with the exception of Charlson comorbidity index (MEM+VAN 4 [2–6] vs. 3 [1–6], P = 0.0002), and exposure to aminoglycosides (MEM+VAN 18.2% vs. 13.2%, P = 0.02) and calcineurin inhibitors (MEM+VAN 6.1% vs. 2.7%, P = 0.002). AKI incidence was similar between group (MEM+VAN 12.8% vs. FEP+VAN 10.8%, P = 0.33). After multivariable logistic regression, there was no significant increase in AKI odds with MEM+VAN compared with FEP+VAN (adjusted odds ratio = 1.02; 95% CI 0.67–1.50). Factors associated with increased AKI odds included: male gender, increased baseline comorbidity, age >80, increased duration of antimicrobial therapy, hypotension, increased baseline renal function, and exposure to aminoglycosides, amphotericin B, non-steroidal anti-inflammatory drugs, loop diuretics, or vasopressors. CONCLUSION: No difference in AKI incidence was found between patients treated with MEM+VAN or FEP+VAN. Other clinical factors, aside from AKI potential, should be considered when choosing between alternatives to piperacillin-tazobactam combined with vancomycin. DISCLOSURES: All authors: No reported disclosures.