Piperacillin-tazobactam versus cefepime incidence of acute kidney injury in combination with vancomycin and tobramycin in pediatric cystic fibrosis patients.

BACKGROUND

Cystic fibrosis (CF) patients often receive prolonged courses of broad spectrum antibiotics, such as piperacillin-tazobactam or cefepime in combination with vancomycin and tobramycin. The objective of this study was to determine the difference in AKI for pediatric CF patients receiving piperacillin-tazobactam or cefepime in combination with vancomycin and tobramycin.

METHODS

IRB approval from a single CF center was obtained for this retrospective cohort study. Charts were evaluated from December 1, 2008 to June 30,2015. Patients were included if they had a diagnosis of CF, age 30 days to 18 years, and received intravenous vancomycin, tobramycin, and piperacillin-tazobactam or cefepime. The primary outcome was difference of AKI incidence in patients receiving piperacillin-tazobactam or cefepime, as defined by modified pediatric risk, injury, failure, loss, end stage renal disease (pRIFLE) criteria.

RESULTS

Seventy-one patients were included with a median (interquartile range) age 11 years (7-16) and weight 36.2 kg (22.7-50). AKI was identified in 54.5% (18/33) of patients receiving piperacillin-tazobactam and 13.2% (5/38) of patients receiving cefepime (P ≤ 0.0001). One patient receiving piperacillin-tazobactam experienced acute renal failure. There was a slight difference in length of admission (13 vs 10 days, P = 0.042), but no difference in days to maximum SCr (6 vs 3, P = 0.127) nor FEV1 percent predicted on admission (69% vs 65%, P = 1.00).

CONCLUSIONS

AKI occurred in nearly 55% of patients with piperacillin-tazobactam therapy versus 13% of patients with cefepime therapy, which suggests cefepime may be preferred in combination with vancomycin and tobramycin for pediatric CF patients.