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Antimicrobial agents and chemotherapy2003; 47(5); 1742-1745; doi: 10.1128/AAC.47.5.1742-1745.2003

In vitro susceptibilities of Rhodococcus equi and other common equine pathogens to azithromycin, clarithromycin, and 20 other antimicrobials.

Abstract: The objective of this study was to determine in vitro activities of azithromycin (AZM), clarithromycin (CLR), and 20 other antimicrobial agents against Rhodococcus equi and other common equine bacterial pathogens. A total of 201 bacterial isolates from various equine clinical samples were examined. CLR was more active than AZM against R. equi, with MICs at which 90% of the isolates were inhibited of 0.12 and 1.0 micro g/ml, respectively. Other antimicrobial agents highly active against at least 90% of R. equi isolates in vitro included rifampin, gentamicin, and imipenem. Both AZM and CLR showed good activity against beta-hemolytic streptococci and Staphylococcus spp. AZM was more active than other macrolides against Pasteurella spp. and Salmonella enterica.
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Publication Date: 2003-04-24 PubMed ID: 12709351PubMed Central: PMC153307DOI: 10.1128/AAC.47.5.1742-1745.2003Google Scholar: Lookup
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  • Journal Article
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  • Non-U.S. Gov't

Summary

This research summary has been generated with artificial intelligence and may contain errors and omissions. Refer to the original study to confirm details provided. Submit correction.

This study focuses on the effectiveness of various antimicrobial agents, including azithromycin and clarithromycin, against Rhodococcus equi, a bacterial pathogen in horses, and other common equine bacterial pathogens.

Research Methodology

  • The researchers examined the antibacterial activities of azithromycin, clarithromycin, and 20 other antimicrobial agents against Rhodococcus equi and other common bacterial pathogens in horses.
  • A total of 201 bacterial isolates were taken from various equine clinical samples for this study.

Findings

  • The study found that, against R. equi, clarithromycin was more active than azithromycin. This conclusion was based on the measurement of MICs (Minimum Inhibitory Concentrations), a measure of the minimum amount of an antimicrobial agent that can inhibit bacterial growth.
  • The researchers recorded MICs at which 90% of R. equi isolates were inhibited by clarithromycin and azithromycin to be 0.12 and 1.0 micro g/ml, respectively.
  • Other antimicrobial agents that the researchers found to be highly active against at least 90% of R. equi isolates in vitro (under lab conditions) included rifampin, gentamicin, and imipenem.

Activity Against Other Bacteria

  • The study also found that both azithromycin and clarithromycin showed significant antibacterial activity against beta-hemolytic streptococci and Staphylococcus spp, other common bacterial pathogens in horses.
  • Azithromycin showed more activity than other macrolides against Pasteurella spp. and Salmonella enterica, two other horse pathogens.

Implications

  • This research can help in choosing the most effective antimicrobial agent in treating bacterial infections in horses.
  • Better understanding of the effectiveness of different antimicrobials against common horse pathogens can lead to improved treatment protocols, potentially leading to better health outcomes for horses and reducing the use of ineffective antimicrobials.

Cite This Article

APA
Jacks SS, Giguère S, Nguyen A. (2003). In vitro susceptibilities of Rhodococcus equi and other common equine pathogens to azithromycin, clarithromycin, and 20 other antimicrobials. Antimicrob Agents Chemother, 47(5), 1742-1745. https://doi.org/10.1128/AAC.47.5.1742-1745.2003

Publication

Antimicrobial agents and chemotherapy
ISSN: 0066-4804
NlmUniqueID: 0315061
Country: United States
Language: English
Volume: 47
Issue: 5
Pages: 1742-1745

Researcher Affiliations

Jacks, Stephanie S
  • Department of Large Animal Clinical Sciences, College of Veterinary Medicine, University of Florida, Gainesville, Florida 32610-0136, USA.
Giguère, Steeve
    Nguyen, An

      MeSH Terms

      • Animals
      • Anti-Bacterial Agents / pharmacology
      • Azithromycin / pharmacology
      • Clarithromycin / pharmacology
      • Horses
      • Microbial Sensitivity Tests
      • Rhodococcus equi / drug effects

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