The Verdict on Vancomycin and Piperacillin/Tazobactam-Associated Nephrotoxicity: Acquittal by Biomarkers or Guilty as Charged?

Current literature largely suggests that the combination of vancomycin and piperacillin/tazobactam (VPT) is associated with a significantly higher risk of acute kidney injury (AKI) compared to vancomycin alone or in combination with other antipseudomonal beta-lactams. However, the true mechanisms behind this potential nephrotoxic effect remain unclear.

The majority of studies describing VPT-associated nephrotoxicity are based on potentially flawed surrogates of glomerular function (e.g., serum creatinine). Moreover, the incidence of creatinine-based AKI is dependent on the consensus definition used. In contrast, animal and clinical studies using more reliable kidney damage biomarkers (e.g., cystatin c) and histopathological examinations largely suggest that injury does not occur.

In the absence of definitive evidence supported by prospective randomized clinical trials specifically designed to address this question and using various GFR markers and AKI biomarkers, the concern of nephrotoxicity should not influence clinical decision-making for patients requiring broad-spectrum antibiotics. Instead, empiric therapy should be guided by the suspected source of infection, local pathogen susceptibility patterns, and adverse effects.