Antimicrobial Resistance in Rhodococcus equi.
Abstract: Pneumonia caused by remains an important cause of disease and death in foals. The combination of a macrolide (erythromycin, azithromycin, or clarithromycin) with rifampin has been the recommended treatment for foals with clinical signs of infection caused by since the early 1980s with, until recently, only rare reports of resistance. Resistance to macrolides and rifampin in isolates of cultured from horses is increasing, with isolates resistant to all macrolides and rifampin now being cultured from up to 40% of infected foals at some farms. This text reviews the available data regarding antimicrobial resistance in , with emphasis on the molecular mechanisms of the recent emergence of resistance to macrolides and rifampin in equine isolates of .
Publication Date: 2017-10-21 PubMed ID: 29052538DOI: 10.1128/microbiolspec.ARBA-0004-2016Google Scholar: Lookup
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- Journal Article
- Review
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- Non-U.S. Gov't
Summary
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This research article examines the increasing resistance to antibiotics in Rhodococcus equi, a bacterium causing pneumonia in foals, with up to 40% of infected foals at some farms hosting bacteria resistant to all recommended treatment options.
Introduction and Research Objective
- The research paper aims to investigate the rising antimicrobial resistance in Rhodococcus equi. Rhodococcus equi is a bacterium that is primarily known for inducing pneumonia in foals, leading to disease and potentially death.
- The article intends to provide an analysis of available data regarding antibiotic resistance in this bacterium, with a particular focus on the recent rise in resistance to macrolides and rifampin.
Contextual Background on Pneumonia in Foals
- Since the 1980s, the combination of a macrolide (such as erythromycin, azithromycin, or clarithromycin) with rifampin has been the recommended treatment for foals showing signs of infection due to Rhodococcus equi.
- So far, resistance to this treatment has rarely been reported. However, recent observations suggest a disturbing change in this trend.
Emergence of Resistance in Treatment
- The research article highlights a growing trend of antibiotic resistance among isolates of Rhodococcus equi cultured from horses. The resistance rate is growing to worrying levels, with bacterial samples from up to 40% of infected foals from some farms proving to be resistant to all macrolides and rifampin.
- The findings are indeed alarming as they mark the increasing impotence of the previously recommended treatment protocol against Rhodococcus equi infection.
Molecular Mechanisms of Emergence of Resistance
- Furthermore, the paper emphasizes understanding the molecular mechanisms that underlie this newly observed resistance.
- The research draws attention towards the need for additional study to understand how this resistance has evolved on a molecular level, which could potentially aid in the development of more effective treatments.
Cite This Article
APA
Giguère S, Berghaus LJ, Willingham-Lane JM.
(2017).
Antimicrobial Resistance in Rhodococcus equi.
Microbiol Spectr, 5(5).
https://doi.org/10.1128/microbiolspec.ARBA-0004-2016 Publication
Researcher Affiliations
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA 30605.
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA 30605.
- Department of Large Animal Medicine, College of Veterinary Medicine, University of Georgia, Athens, GA 30605.
MeSH Terms
- Animal Diseases / drug therapy
- Animal Diseases / microbiology
- Animals
- Anti-Bacterial Agents / pharmacology
- Anti-Bacterial Agents / therapeutic use
- Azithromycin / pharmacology
- Clarithromycin / pharmacology
- Drug Combinations
- Drug Resistance, Bacterial / genetics
- Drug Resistance, Bacterial / physiology
- Erythromycin / pharmacology
- Fluoroquinolones / pharmacology
- Horses
- Lincosamides / therapeutic use
- Macrolides / pharmacology
- Microbial Sensitivity Tests
- Rhodococcus equi / drug effects
- Rhodococcus equi / isolation & purification
- Rifampin / pharmacology
- Streptogramin B / pharmacology
Citations
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