Treatment of Infections Caused by Rhodococcus equi.
Abstract: Pneumonia caused by Rhodococcus equi remains an important cause of disease and death in foals. The combination of a macrolide (erythromycin, azithromycin, or clarithromycin) with rifampin remains the recommended therapy for foals with clinical signs of infection caused by R equi. Most foals with small, subclinical ultrasonographic pulmonary lesions associated with R equi recover without therapy, and administration of antimicrobial agents to these subclinically affected foals does not hasten lesion resolution relative to administration of a placebo. Resistance to macrolides and rifampin in isolates of R equi is increasing.
Copyright © 2016 Elsevier Inc. All rights reserved.
Publication Date: 2017-02-01 PubMed ID: 28161038DOI: 10.1016/j.cveq.2016.11.002Google Scholar: Lookup
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Summary
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The research focuses on the treatment of pneumonia in foals caused by Rhodococcus equi, stating that using a macrolide and rifampin combination is the typical recommended therapy. The study also highlights increasing resistance to these treatments in R. equi isolates.
About Rhodococcus equi
- Rhodococcus equi is a bacterium that causes pneumonia, a serious lung infection, predominantly in foals.
- If left untreated, this infection can often lead to disease and death.
Treatment Strategy
- The research emphasises that the best-named treatment for infections caused by R. equi is a combined therapy of a macrolide (erythromycin, azithromycin, or clarithromycin) and rifampin.
- This is specifically for foals exhibiting clinical signs of the infection.
Subclinical Ultrasonographic Pulmonary Lesions
- The study points out that most foals with small, subclinical ultrasonographic pulmonary lesions associated with R. equi are often to recover without therapy.
- Provision of antimicrobial agents to these foals does not hasten lesion resolution compared to the administration of a placebo. In other words, antibiotics do not necessarily speed up recovery in these mild cases.
Increasing Resistance
- One of the most concerning findings of the study is the increase in resistance to the macrolide-rifampin combination therapy within isolates of R. equi.
- This suggests that these treatments may become less effective over time, posing a significant challenge for preventing and treating infections caused by R. equi in the future.
Cite This Article
APA
Giguère S.
(2017).
Treatment of Infections Caused by Rhodococcus equi.
Vet Clin North Am Equine Pract, 33(1), 67-85.
https://doi.org/10.1016/j.cveq.2016.11.002 Publication
Researcher Affiliations
- Department of Large Animal Medicine, Veterinary Medical Center, University of Georgia, Athens GA 30605. Electronic address: gigueres@uga.edu.
MeSH Terms
- Actinomycetales Infections / drug therapy
- Actinomycetales Infections / veterinary
- Animals
- Anti-Bacterial Agents / therapeutic use
- Azithromycin / therapeutic use
- Clarithromycin / pharmacology
- Drug Resistance, Multiple, Bacterial
- Erythromycin / therapeutic use
- Horse Diseases / drug therapy
- Horse Diseases / microbiology
- Horses
- Pneumonia, Bacterial / drug therapy
- Pneumonia, Bacterial / microbiology
- Pneumonia, Bacterial / veterinary
- Rhodococcus equi / isolation & purification
- Rifampin / pharmacology
Citations
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- Rampacci E, Marenzoni ML, Giovagnoli S, Passamonti F, Coletti M, Pietrella D. Phenotypic Characterization of Rhodococcus equi Biofilm Grown In Vitro and Inhibiting and Dissolving Activity of Azithromycin/Rifampicin Treatment. Pathogens 2019 Dec 4;8(4).
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- Rampacci E, Marenzoni ML, Chiaradia E, Passamonti F, Ricci M, Pepe M, Coletti M, Giovagnoli S. In vitro performances of novel co-spray-dried azithromycin/rifampicin microparticles for Rhodococcus equi disease treatment. Sci Rep 2018 Aug 14;8(1):12149.
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