NEW ORLEANS, LA—In children with cancer, concurrent vancomycin and piperacillin/tazobactam administration may increase risk of acute kidney injury, a retrospective study presented at IDWeek has shown.

These results support recent literature and clinical anecdotes observed in adults, noted Alaina Burns, PharmD, Pharmacy, Children’s Health, Children’s Medical Center Dallas, Dallas, TX.

Due to increased use of these empiric regimens, the study sought to compare the incidence of acute kidney injury in pediatric oncology patients receiving combinations of vancomycin and piperacillin/tazobactam or cefepime.

Dr. Burns and colleagues reviewed charts of children treated in their institution from January 1, 2013, to December 31, 2015. Included were those who received a minimum of 48 hours of combination therapy with vancomycin and piperacillin/tazobactam or cefepime initiated within 48 hours of each other. Excluded were patients with preexisting renal dysfunction or those who had received vasopressors or developed tumor lysis syndrome.

The investigators recorded patient demographics, antibiotic dosing regimens, serum creatinine, and administration of concomitant nephrotoxic medications.

Primary outcome was incidence of acute kidney injury using the Kidney Disease: Improving Global Outcomes (KDIGO) guidelines.

Of 613 charts reviewed, 39 patients met the inclusion criteria, 29 of whom had received piperacillin/tazobactam with vancomycin and 10, cefepime with vancomycin. Median age was 10 years (IQR 2.5–14) and median baseline serum creatinine was 0.4mg/dL (IQR 0.3–0.7).

Both groups had similar characteristics. Twenty-four of the patients had an oncology diagnosis of leukemia, 17 of whom received piperacillin/tazobactam with vancomycin and 7, cefepime with vancomycin (P=0.888).

KDIGO-defined acute kidney injury occurred in 10 (34.5%) patients receiving piperacillin/tazobactam with vancomycin and 2 (20%) receiving cefepime with vancomycin (P=0.406), Dr. Burns concluded. The piperacillin/tazobactam with vancomycin group exhibited a slightly longer median time to AKI than the cefepime and vancomycin group (1.5 days vs. 1 day; P=0.442). 

The findings suggest that clinicians should take into consideration the increased risk of AKI when choosing the appropriate empiric regimen for pediatric oncology patients, Dr. Burns added.