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Polymyxins: wisdom does not always come with age

Zahra Kassamali1, John C Rotschafer, Ronald N Jones

  • 1Department of Pharmacy Practice, University of Illinois-Chicago, 833 S. Wood St., Chicago, IL 60612, USA.

Clinical Infectious Diseases : an Official Publication of the Infectious Diseases Society of America
|June 4, 2013
PubMed

Insights

Polymyxin B potency can vary significantly due to outdated quality control assays, impacting its effectiveness against multidrug-resistant bacteria. Further research is needed to ensure accurate dosing and optimize clinical use of these critical last-line antibiotics.

Area of Science:

  • Pharmacology
  • Microbiology
  • Infectious Diseases

Background:

  • The rise of multidrug-resistant (MDR) bacteria necessitates effective last-line treatments.
  • Polymyxins are crucial last-line agents for MDR bacterial infections.
  • Existing literature often assumes accurate polymyxin product purity and potency.

Purpose of the Study:

  • To review limitations in pharmacological knowledge of polymyxin antimicrobials.
  • To discuss the clinical impact of these limitations.
  • To suggest future research for optimizing polymyxin clinical use.

Main Methods:

  • Literature review focusing on polymyxin pharmacology, purity, and potency.
  • Analysis of quality assurance assay limitations.
  • Discussion of clinical implications.

Main Results:

  • Polymyxin B potency can deviate up to 40% from reported values.
  • Current quality assurance assays, established in the 1940s, are flawed.
  • Inaccurate potency affects reliable dosing and clinical outcomes.

Conclusions:

  • Outdated and flawed quality control assays compromise polymyxin B accuracy.
  • Significant gaps exist in our understanding of polymyxin pharmacology.
  • Further investigation is essential to ensure optimal clinical application of polymyxins.
Keywords:
microbial sensitivity testspolymyxins/pharmacologypolymyxins/therapeutic use

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