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Home / Equine Research Bank / Equine Vet J / Changing policy to treat foals with Rhodococcus equi pneumon...
Equine veterinary journal2020; 52(4); 531-537; doi: 10.1111/evj.13219

Changing policy to treat foals with Rhodococcus equi pneumonia in the later course of disease decreases antimicrobial usage without increasing mortality rate.

Abstract: There is a lack of data on the efficacy of treatment of Rhodococcus equi pneumonia in association with an optimised selection of foals. Objective: To evaluate whether targeted treatment protocols resulting in decreased antimicrobial use impact foal mortality rates. Methods: Retrospective study. Methods: Three hundred and thirty foals with pneumonia per year were randomly selected from 2008 to 2016. All foals were examined once weekly from birth until weaning. A physical examination of the respiratory tract, body temperature, haematology and an ultrasonographic examination of the lungs was included. Sonography areas with visible consolidation were measured and added to calculate an 'abscess score' which represents the extent of pulmonary damage. All weekly medical data were analysed retrospectively. Results: In the period from 2008 to 2011, every foal with pulmonary abscesses was treated. The treatment protocol was changed in 2012 when only foals with larger lesions were treated. Between the two time periods 2008-2011 and 2012-2016, the abscess score at the beginning of treatment increased from a median of 4-11.5 cm. From all foals that developed R equi pneumonia, 81.5% received antibiotic treatment in 2008-2011 (n = 1215) compared with 50.9% in 2012-2016 (n = 1541). The percentage of foals that died from pneumonia or R equi infections did not differ significantly between 2008-2011 and 2012-2016 (0.4% vs 0.6% respectively; P = .6). Conclusions: There was some lack of clarity in old data because this was a retrospective study; therefore, some foals had to be excluded from data analysis. Conclusions: Alteration of treatment criteria, to exclude antibiotic treatment of foals with smaller lesions, has significantly decreased the number of foals being treated without a significant increase in mortality from R equi pneumonia.
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Publication Date: 2020-02-17 PubMed ID: 31808183DOI: 10.1111/evj.13219Google Scholar: Lookup
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  • Journal Article

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.

The research investigates the impact of altering treatment methods for foals with Rhodococcus equi pneumonia, which led to a significant decrease in antimicrobial usage without increasing the mortality rate.

Objective and Methods

  • The primary goal of this study was to establish whether amending treatment protocols for Rhodococcus equi pneumonia in foals, specifically leading to a decline in antimicrobial use, had any effect on their mortality rate.
  • The researchers carried out a retrospective study where 330 foals suffering from pneumonia each year were randomly selected for the study duration from 2008 to 2016.
  • All selected foals were subjected to a weekly examination from the time of their birth until they weaned, which involved a physical inspection of their respiratory tract, body temperature monitoring, haematology, and an ultrasonographic examination of their lungs.
  • A unique ‘abscess score’ was developed by the researchers to represent the extent of lung damage in the foals. This was achieved by measuring and adding up sonography areas that showed visible consolidation.

Results

  • Between 2008 and 2011, every foal diagnosed with pulmonary abscesses was treated. However, from 2012 onward, only foals with larger lesions were given treatment, marking a significant shift in the treatment protocol.
  • The abscess score at the advent of treatment escalated from a median of 4 cm to 11.5 cm between the two periods 2008-2011 and 2012-2016.
  • Out of all the foals diagnosed with R equi pneumonia, 81.5% were given antibiotic treatment in 2008-2011 (n = 1215) compared to 50.9% in 2012-2016 (n = 1541). This is a clear indication of the decrease in antimicrobial usage.
  • Findings show that there was no significant difference in the percentage of foals that succumbed to pneumonia or R equi infections between 2008-2011 and 2012-2016 (0.4% vs 0.6% respectively).

Conclusions

  • Some foals had to be excluded from data analysis due to inconsistencies in the historical data, a limitation introduced by the retrospective nature of the study.
  • The study concluded that modifying treatment criteria to exclude antibiotic treatment for foals with smaller lesions significantly reduces the number of foals being treated, without a noticeable increase in mortality due to R equi pneumonia.

Cite This Article

APA
Arnold-Lehna D, Venner M, Berghaus LJ, Berghaus R, Giguère S. (2020). Changing policy to treat foals with Rhodococcus equi pneumonia in the later course of disease decreases antimicrobial usage without increasing mortality rate. Equine Vet J, 52(4), 531-537. https://doi.org/10.1111/evj.13219

Publication

Equine veterinary journal
ISSN: 2042-3306
NlmUniqueID: 0173320
Country: United States
Language: English
Volume: 52
Issue: 4
Pages: 531-537

Researcher Affiliations

Arnold-Lehna, Denise
  • Equine Clinic, School of Veterinary Medicine, Hannover, Germany.
Venner, Monica
  • Veterinary Clinic, Destedt, Germany.
Berghaus, Londa J
  • Large Animal Medicine, University of Georgia, Athens, Georgia, USA.
Berghaus, Roy
  • Department of Population Health, University of Georgia, Athens, Georgia, USA.
Giguère, Steeve
  • Large Animal Medicine, University of Georgia, Athens, Georgia, USA.

MeSH Terms

  • Actinomycetales Infections / veterinary
  • Animals
  • Anti-Bacterial Agents / therapeutic use
  • Horse Diseases / drug therapy
  • Horses
  • Retrospective Studies
  • Rhodococcus equi

Grant Funding

  • PS Pferdehaltung GmbH

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Citations

This article has been cited 14 times.
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