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Antimicrobial Synergy Testing by the Inkjet Printer-assisted Automated Checkerboard Array and the Manual Time-kill Method
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Combination therapy for treatment of infections with gram-negative bacteria

Pranita D Tamma1, Sara E Cosgrove, Lisa L Maragakis

  • 1The Johns Hopkins Medical Institutions, Department of Medicine, Division of Pediatric Infectious Diseases, Baltimore, Maryland, USA. ptamma1@jhmi.edu

Clinical Microbiology Reviews
|July 6, 2012
PubMed

Insights

Combination antibiotic therapy is beneficial for empiric treatment of Gram-negative infections, especially with rising multidrug-resistant organisms. Its value diminishes once susceptibility data is known.

Area of Science:

  • Infectious Diseases
  • Pharmacology
  • Critical Care Medicine

Background:

  • Combination antibiotic therapy is common for severe Gram-negative infections.
  • Rising multidrug-resistant Gram-negative organisms support empiric combination use.
  • The benefit of continued combination therapy post-susceptibility testing is debated.

Purpose of the Study:

  • To review evidence comparing monotherapy and combination therapy for Gram-negative infections.
  • To evaluate the role of combination therapy in empiric versus definitive treatment.

Main Methods:

  • Systematic review of existing literature.
  • Comparison of outcomes between monotherapy and combination therapy groups.
  • Analysis of data regarding empiric and targeted treatment strategies.

Main Results:

  • Combination therapy increases the likelihood of effective empiric treatment.
  • Evidence for in vitro synergy or resistance prevention during definitive treatment is limited.
  • Greatest benefit observed during the empiric phase of treatment.

Conclusions:

  • Combination antibiotic therapy is most advantageous during the empiric treatment of Gram-negative infections.
  • Continued combination therapy after susceptibility results is controversial.
  • Focus on effective empiric agent selection is key.

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