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Journal of veterinary internal medicine2012; 27(1); 171-176; doi: 10.1111/jvim.12030

Efficacy of mass antimicrobial treatment of foals with subclinical pulmonary abscesses associated with Rhodococcus equi.

Abstract: Mass antimicrobial treatment of foals with small subclinical ultrasonographic pulmonary lesions is empirical practice on many farms with endemic disease caused by Rhodococcus equi. Objective: Mass antimicrobial treatment of foals with subclinical ultrasonographic pulmonary lesions is unnecessary. Methods: One hundred and eight foals on a farm endemic for infections caused by R. equi. Methods: Controlled, randomized, and double-blinded prospective study. Foals with ultrasonographic evidence of pulmonary abscesses 5.0-10 cm in diameter (n = 108) were randomly allocated in 5 treatment groups: (1) tulathromycin IM; (2) doxycycline monotherapy PO; (3) doxycycline with rifampin PO; (4) azithromycin with rifampin PO, and (5) saline IM as a placebo. Physical examination and thoracic ultrasonography were performed by individuals unaware of treatment group assignment. Foals with evidence of disease progression were removed from the study and treated with azithromycin-rifampin. Results: Overall, 22/25 (88%) foals in the placebo group recovered without the need for treatment. The proportion of foals that had evidence of disease progression did not differ significantly between the treatment groups (P > .05). Although the median duration of treatment was significantly (P < .05) shorter in foals treated with azithromycin-rifampin (46 days) compared with foals treated with the placebo (73 days), the time frame of ultrasonographic lesion resolution did not differ significantly between the treatment groups. Conclusions: The majority of foals with subclinical pulmonary abscesses <10 cm in diameter recover without antimicrobial treatment and treatment of affected foals does not provide a clear benefit over administration of a placebo.
Copyright © 2012 by the American College of Veterinary Internal Medicine.
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Publication Date: 2012-12-28 PubMed ID: 23278131DOI: 10.1111/jvim.12030Google Scholar: Lookup
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  • Journal Article
  • Randomized Controlled Trial

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 research investigates the effectiveness of mass antimicrobial treatment on foals with subclinical pulmonary abscesses caused by Rhodococcus equi. The results indicate that most foals affected recover without needing such treatment and there seems to be no clear advantage over administration of a placebo.

Study Methodology

  • The study was a controlled, randomized, and double-blind trial conducted on a farm with an endemic presence of infections caused by Rhodococcus equi.
  • A total of 108 foals possessing ultrasonographic evidence of pulmonary abscesses ranging from 5.0-10 cm in diameter were included.
  • These foals were randomly divided into five groups which were administered different treatments: (1) Tulathromycin IM, (2) Doxycycline monotherapy PO, (3) Doxycycline with Rifampin PO, (4) Azithromycin with Rifampin PO, and (5) Saline IM as a placebo.
  • Physical examinations and thoracic ultrasonography were performed by individuals who were kept unaware of the treatment group assignments.
  • Foals that showed disease progression were removed from the study and treated with Azithromycin-Rifampin.

Study Findings

  • From the findings, it was observed that 88% of the foals in the placebo group recovered without needing treatment.
  • The rate of disease progression did not significantly differ between the various treatment groups.
  • While the median duration of treatment was significantly shorter in foals treated with Azithromycin-Rifampin (46 days) compared to those treated with the placebo (73 days), the time taken for the ultrasonographic lesions to resolve did not vary significantly between the groups.

Conclusion

  • The findings suggest that the majority of foals with subclinical pulmonary abscesses less than 10 cm in diameter are likely to recover without antimicrobial treatment.
  • The study also found that providing treatment to affected foals does not confer any clear advantage compared to using a placebo.

This study’s findings could influence the treatment protocols in farms with a high prevalence of Rhodococcus equi, potentially reducing unnecessary use of antimicrobials.

Cite This Article

APA
Venner M, Astheimer K, Lämmer M, Giguère S. (2012). Efficacy of mass antimicrobial treatment of foals with subclinical pulmonary abscesses associated with Rhodococcus equi. J Vet Intern Med, 27(1), 171-176. https://doi.org/10.1111/jvim.12030

Publication

Journal of veterinary internal medicine
ISSN: 1939-1676
NlmUniqueID: 8708660
Country: United States
Language: English
Volume: 27
Issue: 1
Pages: 171-176

Researcher Affiliations

Venner, M
  • Veterinary Clinic, Destedt, Germany.
Astheimer, K
    Lämmer, M
      Giguère, S

        MeSH Terms

        • Actinomycetales Infections / drug therapy
        • Actinomycetales Infections / veterinary
        • Animals
        • Anti-Bacterial Agents / therapeutic use
        • Double-Blind Method
        • Female
        • Horse Diseases / drug therapy
        • Horse Diseases / microbiology
        • Horses
        • Lung Abscess / drug therapy
        • Lung Abscess / veterinary
        • Male
        • Rhodococcus equi
        • Treatment Outcome

        Citations

        This article has been cited 21 times.
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