Outcome analysis of colistin-treated burn center patients

Intravenous colistimethate sodium (CMS) use in burn center patients is increasing due to the emergence of multidrug-resistant gram-negative bacteria. However, optimal dosing strategies and factors that may contribute to treatment failure are limited. The purpose of this study was to determine factors that may contribute to treatment failure in colistin-treated burn center patients.

This retrospective, observational study included burn center patients that received ≥48h of intravenous CMS between June 1, 2009 and June 30, 2014. Data was collected utilizing the institution's electronic medical record system. Statistical analysis included demographic, univariable, and multivariable analysis to determine factors that may predict clinical failure of burn center patients requiring intravenous CMS.

Eighty-one patients were included in this study, with 55 patients (68%) achieving clinical success. A total daily dose (TDD) of >5mg/kg ideal body weight (IBW) was associated with significantly less clinical failure (odds ratio=0.21; 95% CI, 0.05, 0.91). Additionally, clinical failure was significantly higher in patients with wounds as the primary source of infection, creatinine clearances of 91-120mL/min, and those receiving renal replacement therapy. No difference was observed in nephrotoxicity when comparing TDD >5mg/kg IBW and TDD ≤5mg/kg IBW.

Clinical success was significantly higher with larger intravenous CMS doses in burn center patients. Higher CMS doses were not found to be associated with increased nephrotoxicity within this patient group.