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New information about the polymyxin/colistin class of antibiotics

José Molina1, Elisa Cordero, Jerónimo Pachón

  • 1University Hospital Virgen del Rocío, Institute of Biomedicine of Sevilla, Infectious Diseases Service, Av. Manuel Siurot s/n, 41013, Sevilla, Spain.

Expert Opinion on Pharmacotherapy
|November 26, 2009
PubMed

Insights

Multidrug-resistant Gram-negative bacilli (MDR-GNB) infections pose a significant threat in ICUs. This review discusses polymyxins as a key treatment option, exploring strategies to enhance their effectiveness against resistant bacteria.

Area of Science:

  • Infectious Diseases
  • Critical Care Medicine
  • Pharmacology

Background:

  • Multidrug-resistant Gram-negative bacilli (MDR-GNB) infections are a major cause of morbidity and mortality in intensive care units (ICUs).
  • Limited therapeutic options exist due to widespread antimicrobial resistance.
  • Tigecycline has limitations, and older antibiotics like colistin are often the only remaining choices.

Purpose of the Study:

  • To review the latest data on polymyxins for treating MDR-GNB infections.
  • To discuss strategies for improving polymyxin efficacy and addressing resistance.
  • To highlight the reintroduction and evolving clinical use of polymyxins.

Main Methods:

  • Literature review of recent data on polymyxins.
  • Analysis of new pharmaceutical formulations and dosage regimens.
  • Discussion of strategies to enhance polymyxin effectiveness.

Main Results:

  • New polymyxin formulations have reduced toxicity, enabling their reintroduction.
  • Polymyxin effectiveness remains suboptimal, with concerns about heteroresistance and pan-drug-resistant strains.
  • Various approaches, including improved dosing and synergistic combinations, are being explored to enhance polymyxin activity.

Conclusions:

  • Polymyxins are crucial for treating MDR-GNB infections, but challenges remain.
  • Ongoing research focuses on optimizing polymyxin use through improved administration and combination therapies.
  • Addressing polymyxin resistance and suboptimal efficacy is critical for improving outcomes in critically ill patients.

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