Incidence and predictors of acute kidney injury associated with intravenous polymyxin B therapy.
BACKGROUND
Increases in multidrug-resistance among gram-negative organisms have necessitated the use of polymyxins. To date, the incidence of acute kidney injury (AKI) associated with polymyxin B has not been evaluated using RIFLE criteria.


METHODS
Adult patients who received polymyxin B were retrospectively evaluated to determine the incidence of AKI during polymyxin B therapy using RIFLE criteria. Predictors of AKI were identified by comparing characteristics of patients with and without AKI.


RESULTS
A total of 73 patients were included. The incidence of AKI was 60%. Ten (14%) patients discontinued therapy due to nephrotoxicity. Median duration of polymyxin B was 11 days with a median cumulative dose of 18 mg/kg. Concomitant nephrotoxins were received in 69 (95%). Patients with AKI had a higher median cumulative dose (1578 mg vs. 800 mg; p = 0.02), a higher body mass index (BMI) (27.2 vs. 24.5 kg/m(2); p = 0.03), and were more likely to receive vancomycin (82% vs. 55%; p = 0.03) compared to those without AKI. After controlling for polymyxin B duration, independent predictors of AKI were higher BMI and concomitant vancomycin.


CONCLUSIONS
The incidence of AKI during polymyxin B therapy was 60%. Further studies are needed to define dosing parameters that maximize efficacy and minimize nephrotoxicity.
Department of Pharmacy, New York-Presbyterian Hospital, 630 W. 168th Street, New York, NY 10032, USA. cck27@columbia.edu
Christine J
CJ
Kubin
Tanya M
TM
Ellman
Varun
V
Phadke
Laura J
LJ
Haynes
David P
DP
Calfee
Michael T
MT
Yin
D058186:Acute Kidney Injury / Q000139:chemically induced* / Q000453:epidemiology*; D000328:Adult; D000368:Aged; D000900:Anti-Bacterial Agents / Q000008:administration & dosage* / Q000009:adverse effects*; D015331:Cohort Studies; D005260:Female; D006801:Humans; D015994:Incidence; D008297:Male; D008875:Middle Aged; D011112:Polymyxin B / Q000008:administration & dosage* / Q000009:adverse effects*; D012189:Retrospective Studies; D012307:Risk Factors
D000900:Anti-Bacterial Agents; D011112:Polymyxin B