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.
Publication Date: 2020-02-17 PubMed ID: 31808183DOI: 10.1111/evj.13219Google Scholar: Lookup
The Equine Research Bank provides access to a large database of publicly available scientific literature. Inclusion in the Research Bank does not imply endorsement of study methods or findings by Mad Barn.
  • 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, Giguu00e8re 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

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.
Giguu00e8re, 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

References

This article includes 39 references
  1. Cohen ND. Causes of and farm management factors associated with disease and death in foals. J Am Vet Med Assoc. 1994;204:1644-51.
  2. Muscatello G. Rhodococcus equi pneumonia in the foal - Part 1: pathogenesis and epidemiology. Vet J. 2012;192:20-6.
  3. Hoffman AM, Viel L, Prescott JF, Rosendal S, Thorsen J. Association of microbiologic flora with clinical, endoscopic, and pulmonary cytologic findings in foals with distal respiratory tract infection. Am J Vet Res. 1993;54:1615-22.
  4. Giguu00e8re S, Gaskin J, Miller C, Bowman JL. Evaluation of a commercially available hyperimmune plasma product for prevention of naturally acquired pneumonia caused by Rhodococcus equi in foals. J Am Vet Med Assoc. 2002;220:59-63.
  5. Slovis NM, McCracken J, Mundy G. How to use thoracic ultrasound to screen foals for Rhodococcus equi at affected farms. Proc Am Assoc Equine Practnrs. 2005;51:274-8.
  6. McCracken JL, Slovis NM. Use of thoracic ultrasound for the prevention of Rhodococcus equi pneumonia on endemic farms. Proc Am Assoc Equine Practnrs. 2009;55:38-44.
  7. Venner M, Kerth R, Klug E. Evaluation of tulathromycin in the treatment of pulmonary abscesses in foals. Vet J. 2007;174:418-21.
  8. Venner M, Credner N, Lu00e4mmer M, Giguu00e8re S. Comparison of tulathromycin, azithromycin and azithromycin-rifampin for the treatment of mild pneumonia associated with Rhodococcus equi. Vet Rec. 2013;173:397.
  9. Hildebrand F, Venner M, Giguu00e8re S. Efficacy of gamithromycin for the treatment of foals with mild to moderate bronchopneumonia. J Vet Intern Med. 2015;29:333-8.
  10. Rutenberg D, Venner M, Giguu00e8re S. Efficacy of tulathromycin for the treatment of foals with mild to moderate bronchopneumonia. J Vet Intern Med. 2017;31:901-6.
  11. Giguu00e8re S, Lee E, Williams E, Cohen ND, Chaffin MK, Halbert N, et al. Determination of the prevalence of antimicrobial resistance to macrolide antimicrobials or rifampin in Rhodococcus equi isolates and treatment outcome in foals infected with antimicrobial-resistant isolates of R. equi. J Am Vet Med Assoc. 2010;237:74-81.
  12. Meyer-Hamme MB. Rhodococcus equi and Streptococcus equi subsp. zooepidemicus in nasal swabs and tracheobronchial secretions of foals with pulmonary disease. Thesis, Veterinary School of Hannover. 2004; p. 112.
  13. Venner M, Meyer-Hamme B, Verspohl J, Hatori F, Shimizu N, Sasaki Y, et al. Genotypic characterization of VapA positive Rhodococcus equi in foals with pulmonary affection and their soil environment on a warmblood horse breeding farm in Germany. Res Vet Sci. 2007;83:311-7.
  14. Rothaar E. On the development of antibiotic sensitivity by R. equi. Thesis, Veterinary School of Hannover. 2006; p. 118.
  15. Venner M, Heyers P, Strutzberg-Minder K, Lorenz N, Verspohl J, Klug E. Detection of Rhodococcus equi by microbiological culture and by polymerase chain reaction in samples of tracheobronchial secretions of foals. Berl Munch Tierarztl Wochenschr. 2007;120:126-33.
  16. Neudert N. Comparison of the detection of Rhodococcus equi by microbiological culture, polymerase chain reaction (PCR) and cytology in tracheobronchial fluid from foals. Thesis, Veterinary School of Hannover, 2007; p. 109.
  17. Hollberg A. Examination of antibiotic sensitivity by Rhodococcus equi in german foals. Thesis, Veterinary School of Hannover, 2011; p. 69.
  18. Laemmer M. Detection of Rhodococcus equi in faeces and tracheobronchial secretions of foals on a farm with endemic rhodococcosis: comparison of healthy foals and foals with pulmonary abscesses. Schedding-Havemeyer symposium Rhodococcus, Edinburgh; 2008.
  19. Kilian K. Comparative studies of the detection of Rhodococcus equi in the breath, in tracheobronchial fluids and in faeces of foals. Thesis, Veterinary School of Hannover, 2008; p. 128.
  20. Hagist C. Genotyping of Rhodococcus equi strains isolated in Germany. Thesis, Veterinary School of Hannover, 2016; p. 82.
  21. Weimar BM. Lung abscesses in foals: Evaluation of clinical, ultrasonic, endoscopical, pathomorphological and microbiological findings. Thesis, Veterinary School of Hannover, 2006; p. 157.
  22. Venner M, Reinhold B, Beyerbach M, Feige K. Efficacy of azithromycin in preventing pulmonary abscesses in foals. Vet J. 2009;179:301-3.
  23. Giguu00e8re S, Cohen ND, Chaffin MK, Slovis NM, Hondalus MK, Hines SA, et al. Diagnosis, treatment, control, and prevention of infections caused by Rhodococcus equi in foals. J Vet Intern Med. 2011;25:1209-20.
  24. Venner M, Ru00f6diger A, Lu00e4mmer M, Giguu00e8re S. Failure of antimicrobial therapy to accelerate spontaneous healing of subclinical pulmonary abscesses on a farm with endemic infections caused by Rhodococcus equi. Vet J. 2012;192:293-8.
  25. Venner M, Astheimer K, Lu00e4mmer M, Giguu00e8re S. Efficacy of mass antimicrobial treatment of foals with subclinical pulmonary abscesses associated with Rhodococcus equi. J Vet Intern Med. 2013;27:171-6.
  26. Chaffin MK, Cohen ND, Martens RJ. Evaluation of equine breeding farm characteristics as risk factors for development of Rhodococcus equi pneumonia in foals. J Am Vet Med Assoc. 2003;222:467-75.
  27. Cohen ND, O'Conor MS, Chaffin MK, Martens RJ. Farm characteristics and management practices associated with development of Rhodococcus equi pneumonia in foals. J Am Vet Med Assoc. 2005;226:404-13.
  28. Chaffin MK, Cohen ND, Martens RJ. Evaluation of equine breeding farm management and preventative health practices as risk factors for development of Rhodococcus equi pneumonia in foals. J Am Vet Med Assoc. 2003;222:476-85.
  29. Martens RJ, Takai S, Cohen ND, Chaffin MK, Liu H, Sakurai K, et al. Association of disease with isolation and virulence of Rhodococcus equi from farm soil and foals with pneumonia. J Am Vet Med Assoc. 2000;217:220-5.
  30. Chaffin MK, Cohen ND, Martens RJ, Edwards RF, Nevill M. Foal-related risk factors associated with development of Rhodococcus equi pneumonia on farms with endemic infection. J Am Vet Med Assoc. 2003;223:1791-9.
  31. Gressler LT, Machado G, Silveira BP, Cohen ND, Corbellini LG, Leotti VB, et al. Prevalence of Rhodococcus equi from the nasal cavity of 1010 apparently healthy horses. Equine Vet J. 2018;50:667-71.
  32. Lavoie JP, Fiset L, Laverty S. Review of 40 cases of lung abscesses in foals and adult horses. Equine Vet J. 1994;26:348-52.
  33. Hillidge CJ. Use of erythromycin-rifampin combination in treatment of Rhodococcus equi pneumonia. Vet Microbiol. 1987;14:337-42.
  34. Pusterla N, Wilson WD, Mapes S, Leutenegger CM. Diagnostic evaluation of real-time PCR in the detection of Rhodococcus equi in faeces and nasopharyngeal swabs from foals with pneumonia. Vet Rec. 2007;161:272-5.
  35. Sellon DC, Besser TE, Vivrette SL, McConnico RS. Comparison of nucleic acid amplification, serology, and microbiologic culture for diagnosis of Rhodococcus equi pneumonia in foals. J Clin Microbiol. 2001;39:1289-93.
  36. Nordmann P, Ronco E. In-vitro antimicrobial susceptibility of Rhodococcus equi. J Antimicrob Chemother. 1992;29:383-93.
  37. Prescott JF, Nicholson VM. The effects of combinations of selected antibiotics on the growth of Corynebacterium equi. J Vet Pharmacol Ther. 1984;7:61-4.
  38. Berghaus LJ, Giguu00e8re S, Guldbech K. Mutant prevention concentration and mutant selection window for 10 antimicrobial agents against Rhodococcus equi. Vet Microbiol. 2013;166:670-5.
  39. Burton AJ, Giguu00e8re S, Sturgill TL, Berghaus LJ, Slovis NM, Whitman JL, et al. Macrolide- and rifampin-resistant Rhodococcus equi on a horse breeding farm, Kentucky, USA. Emerg Infect Dis. 2013;19:282.

Citations

This article has been cited 7 times.
  1. Knox A, Zerna G, Beddoe T. Current and Future Advances in the Detection and Surveillance of Biosecurity-Relevant Equine Bacterial Diseases Using Loop-Mediated Isothermal Amplification (LAMP).. Animals (Basel) 2023 Aug 18;13(16).
    doi: 10.3390/ani13162663pubmed: 37627456google scholar: lookup
  2. Rakowska A, Marciniak-Karcz A, Bereznowski A, Cywiu0144ska A, u017bychska M, Witkowski L. Less Typical Courses of Rhodococcus equi Infections in Foals.. Vet Sci 2022 Oct 31;9(11).
    doi: 10.3390/vetsci9110605pubmed: 36356082google scholar: lookup
  3. Sting R, Schwabe I, Kieferle M, Mu00fcnch M, Rau J. Fatal Infection in an Alpaca (Vicugna pacos) Caused by Pathogenic Rhodococcus equi.. Animals (Basel) 2022 May 19;12(10).
    doi: 10.3390/ani12101303pubmed: 35625149google scholar: lookup
  4. Nielsen SS, Bicout DJ, Calistri P, Canali E, Drewe JA, Garin-Bastuji B, Gonzales Rojas JL, Gortu00e1zar C, Herskin M, Michel V, Miranda Chueca Mu00c1, Padalino B, Pasquali P, Roberts HC, Spoolder H, Stu00e5hl K, Velarde A, Viltrop A, Winckler C, Baldinelli F, Broglia A, Kohnle L, Alvarez J. Assessment of listing and categorisation of animal diseases within the framework of the Animal Health Law (Regulation (EU) No 2016/429): antimicrobial-resistant Rhodococcus equi in horses.. EFSA J 2022 Feb;20(2):e07081.
    doi: 10.2903/j.efsa.2022.7081pubmed: 35136423google scholar: lookup
  5. Kahn SK, Cywes-Bentley C, Blodgett GP, Canaday NM, Turner-Garcia CE, Flores-Ahlschwede P, Metcalfe LL, Nevill M, Vinacur M, Sutter PJ, Meyer SC, Bordin AI, Pier GB, Cohen ND. Randomized, controlled trial comparing Rhodococcus equi and poly-N-acetyl glucosamine hyperimmune plasma to prevent Ru2009equi pneumonia in foals.. J Vet Intern Med 2021 Nov;35(6):2912-2919.
    doi: 10.1111/jvim.16294pubmed: 34738651google scholar: lookup
  6. u00c1lvarez-Narvu00e1ez S, Huber L, Giguu00e8re S, Hart KA, Berghaus RD, Sanchez S, Cohen ND. Epidemiology and Molecular Basis of Multidrug Resistance in Rhodococcus equi.. Microbiol Mol Biol Rev 2021 May 19;85(2).
    doi: 10.1128/MMBR.00011-21pubmed: 33853933google scholar: lookup
  7. Rakowska A, Cywinska A, Witkowski L. Current Trends in Understanding and Managing Equine Rhodococcosis.. Animals (Basel) 2020 Oct 18;10(10).
    doi: 10.3390/ani10101910pubmed: 33081047google scholar: lookup