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Published on: April 18, 2019

Polymyxin B nephrotoxicity and efficacy against nosocomial infections caused by multiresistant gram-negative bacteria

John P Ouderkirk1, Jill A Nord, Glenn S Turett

  • 1Section of Infectious Diseases, Department of Medicine, Saint Vincent's Hospital--Manhattan, New York, New York 10011, USA.

Antimicrobial Agents and Chemotherapy
|July 25, 2003
PubMed

Insights

Systemic polymyxin B effectively treats multiresistant gram-negative infections. While 14% of patients experienced nephrotoxicity, it was linked to older age, not drug dosage, suggesting a safer profile than previously reported.

Area of Science:

  • Infectious Diseases
  • Nephrology
  • Pharmacology

Background:

  • Polymyxins, including polymyxin B, are crucial for treating infections caused by multidrug-resistant gram-negative bacteria.
  • Previous studies reported variable rates of nephrotoxicity with systemic polymyxin use.
  • The re-emergence of multidrug-resistant infections necessitates a clear understanding of polymyxin B's safety profile.

Purpose of the Study:

  • To retrospectively investigate the incidence of nephrotoxicity in patients receiving parenteral polymyxin B.
  • To evaluate the clinical and microbiologic efficacy of polymyxin B in treating infections caused by multidrug-resistant gram-negative bacteria.
  • To identify factors associated with the development of renal toxicity.

Main Methods:

  • Retrospective analysis of 60 patients treated with parenteral polymyxin B from October 1999 to September 2000.
  • Collection of demographic and clinical data, including baseline renal function, daily and cumulative drug doses, and treatment duration.
  • Assessment of renal toxicity, clinical outcomes, microbiologic clearance, and mortality.

Main Results:

  • Nephrotoxicity, defined as renal failure, occurred in 14% of patients, all with normal baseline renal function.
  • Development of renal failure was significantly associated with older age (76 vs. 59 years; P = 0.02) and independent of drug dosage or treatment duration.
  • Overall mortality was 20%, increasing to 57% in patients who developed renal failure. Microbiologic clearance was achieved in 88% of patients.

Conclusions:

  • Systemic polymyxin B is highly effective for treating multidrug-resistant gram-negative bacterial infections.
  • The observed rate of nephrotoxicity (14%) is lower than previously described in the literature.
  • Older age is a significant risk factor for polymyxin B-induced nephrotoxicity, while dosage and duration do not appear to be.
  • Polymyxin B remains a valuable therapeutic option for challenging infections, with careful patient selection advised.

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