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Published on: December 14, 2016

In vitro antimicrobial activity of rifaximin against enteropathogens causing traveler's diarrhea

Joaquim Ruiz1, Laura Mensa, Cristina O'Callaghan

  • 1Hospital Clinic, Centro de Salud Internacional (CRESIB); IDIBAPS, Universitat de Barcelona, 08036-Barcelona, Spain. joruiz@clinic.ub.es

Diagnostic Microbiology and Infectious Disease
|September 25, 2007
PubMed

Insights

Rifaximin shows strong in vitro activity against common causes of traveler's diarrhea, including diarrheagenic Escherichia coli and Shigella sonnei. This suggests rifaximin is a promising antibiotic option for treating these gastrointestinal infections.

Area of Science:

  • Microbiology
  • Infectious Diseases
  • Pharmacology

Background:

  • Traveler's diarrhea is a common illness often caused by bacterial pathogens.
  • Diarrheagenic Escherichia coli and Shigella sonnei are frequent culprits of traveler's diarrhea.
  • Effective antibiotic treatment is crucial for managing these infections.

Purpose of the Study:

  • To evaluate the in vitro antimicrobial activity of rifaximin.
  • To compare rifaximin's efficacy against other antimicrobial agents.
  • To assess the potential of rifaximin for treating traveler's diarrhea.

Main Methods:

  • In vitro susceptibility testing was performed.
  • Minimum Inhibitory Concentrations (MICs) were determined for rifaximin.
  • Pathogens tested included 84 diarrheagenic Escherichia coli strains and 11 Shigella sonnei strains.

Main Results:

  • Rifaximin demonstrated significant in vitro activity against the tested pathogens.
  • The MIC of rifaximin ranged from <0.007 to 32 mg/L.
  • Other tested antimicrobial agents showed higher MICs, often exceeding 256 mg/L.

Conclusions:

  • Rifaximin exhibits potent antimicrobial effects against key pathogens causing traveler's diarrhea.
  • The low MIC values indicate rifaximin's potential as an effective treatment.
  • Rifaximin represents a promising therapeutic option for traveler's diarrhea.

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