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Home / Equine Research Bank / Aust Vet J / The relationship between bronchoalveolar lavage fluid cytolo...
Australian veterinary journal2019; 97(9); 343-350; doi: 10.1111/avj.12861

The relationship between bronchoalveolar lavage fluid cytology and airway hyper-reactivity in a population of Australian horses presented for poor performance.

Abstract: To investigate the relationship between bronchoalveolar lavage fluid cytology, particularly mast cells, and airway hyper-reactivity in athletic horses presented for poor performance that included a respiratory tract evaluation in two disparate locations in Australia. Methods: Multi-centre, retrospective and prospective cross-sectional study METHODS: Eighty four adult horses underwent both pulmonary function testing and histamine bronchoprovocation with a commercial flowmetric plethysmography system. A bronchoalveolar lavage was performed four to twelve hours later. Bronchoalveolar lavage fluid cytology was categorised using two differing classification systems to define mild equine asthma. Statistical analysis was used to assess associations between bronchoalveolar lavage fluid relative inflammatory cell percentages, and airway hyper-reactivity and their associated categorisations. Results: Sixty four percent (54/84) of horses displayed airway hyper-reactivity, as defined by PC  < 6 mg/ml of histamine. A relative mastocytosis was the most common bronchoalveolar lavage fluid cytological abnormality. Horses with a sole mast cell response of ≥ 5% within their bronchoalveolar lavage fluid displayed airway hyper-reactivity at a lower dose of nebulized histamine than horses with normal bronchoalveolar lavage fluid cytology. Horses with mixed cell responses (relative mast cell percentage > 2% and/or relative neutrophil percentage > 5% and/or eosinophil relative cell percentage ≥ 1%) displayed airway hyper-reactivity at a lower dose of nebulized histamine than horses with normal bronchoalveolar lavage fluid cytology. Conclusions: In the Australian context, recently revised increased bronchoalveolar lavage fluid cytology relative cell percentage cut offs appear appropriate for sole mast cell responses. The historical lower cut offs appear to be appropriate for mixed inflammatory cell responses.
© 2019 Australian Veterinary Association.
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Publication Date: 2019-07-08 PubMed ID: 31286483DOI: 10.1111/avj.12861Google Scholar: Lookup
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  • Comparative Study
  • 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.

This research evaluated the correlation between the composition of bronchoalveolar lavage fluid (the fluid obtained from lung washes) and airway over-responsiveness in athletic horses that have been performing poorly, in Australia. The study discovered that the overactivity of the airway is heavily associated with anomalous increases in specific cells found within the bronchoalveolar lavage fluid.

Study Design & Methodology

  • The researchers carried out a multi-centre study, collecting retrospective and prospective cross-sectional data from 84 adult horses.
  • The horses underwent pulmonary function testing as well as histamine bronchoprovocation via a commercial flowmetric plethysmography system. The latter test measures the change in airway diameter in response to an inhaled histamine dose.
  • Each horse had a bronchoalveolar lavage performed between four and twelve hours post testing, with the fluid collected being analysed for cell types.
  • Two different classification systems were used on the cell composition in the fluid for the diagnosis of mild equine asthma.

Findings & Interpretations

  • Approximately 64% of the horses showed over-responsive airways, as indicated by a histamine sensitivity threshold of less than 6 mg/ml.
  • An abnormally high concentration of mast cells (a type of white blood cell) was the most common anomaly found in the bronchoalveolar lavage fluid cytology.
  • Horses that had an increased mast cell response of 5% or more within their bronchoalveolar lavage fluid exhibited airway over-reactivity at a lower dose of nebulized histamine compared to horses with normal fluid cytology.
  • Similarly, horses showing mixed cell responses displayed airway over-reactivity at a lower dose of nebulized histamine compared to horses with normal fluid cytology.

Conclusion and Implications

  • The study suggests that the recent revision to higher cut-offs for cell percentage in bronchoalveolar lavage fluid cytology is appropriate for diagnostic cases solely related to mast cells.
  • The original, lower cut-offs seem to be apt for diagnoses involving mixed inflammatory cell responses.
  • The study’s findings highlight the importance of understanding cell percentages in bronchoalveolar lavage fluid for managing and treating airway problems in horses, particularly those in demanding athletic roles.

Cite This Article

APA
Secombe CJ, van Eps AW, Bruce M, Lester GD. (2019). The relationship between bronchoalveolar lavage fluid cytology and airway hyper-reactivity in a population of Australian horses presented for poor performance. Aust Vet J, 97(9), 343-350. https://doi.org/10.1111/avj.12861

Publication

Australian veterinary journal
ISSN: 1751-0813
NlmUniqueID: 0370616
Country: England
Language: English
Volume: 97
Issue: 9
Pages: 343-350

Researcher Affiliations

Secombe, C J
  • School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia.
van Eps, A W
  • Equine Specialist Hospital, School of Veterinary Science, The University of Queensland, Gatton, Queensland, Australia.
Bruce, M
  • School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia.
Lester, G D
  • School of Veterinary Medicine, College of Science, Health, Engineering and Education, Murdoch University, 90 South Street, Murdoch, Western Australia, Australia.

MeSH Terms

  • Animals
  • Asthma / epidemiology
  • Asthma / physiopathology
  • Asthma / veterinary
  • Athletic Performance / physiology
  • Australia / epidemiology
  • Bronchoalveolar Lavage
  • Bronchoalveolar Lavage Fluid / cytology
  • Cross-Sectional Studies
  • Horse Diseases / epidemiology
  • Horse Diseases / physiopathology
  • Horses
  • Respiratory Function Tests / veterinary
  • Respiratory Hypersensitivity / epidemiology
  • Respiratory Hypersensitivity / physiopathology
  • Respiratory Hypersensitivity / veterinary

Grant Funding

  • Rural Industries Research and Development Corporation

References

This article includes 33 references
  1. Allen KJ, Tremaine WH, Franklin SH. Prevalence of inflammatory airway disease in national hunt horses referred for investigation of poor athletic performance. Equine Vet J Suppl 2006;36:529-534.
  2. Richard EA, Fortier GD, Pitel PH. Sub-clinical diseases affecting performance in standardbred trotters: Diagnostic methods and predictive parameters. Vet J 2010;184:282-289.
  3. Nolen-Walston RD, Harris M, Agnew ME. Clinical and diagnostic features of inflammatory airway disease subtypes in horses examined because of poor performance: 98 cases (2004-2010). JAVMA 2013;242:1138-1145.
  4. Wichtel M, Gomez D, Burton S. Relationships between equine airway reactivity measured by flowmetric plethysmography and specific indicators of airway inflammation in horses with suspected inflammatory airway disease. Equine Vet J 2016;48:466-471.
  5. Ivester KM, Couëtil LL, Moore GE. An observational study of environmental exposures, airway cytology, and performance in racing thoroughbreds. J Vet Intern Med 2018;32:1754-1762.
  6. Couëtil LL, Cardwell JM, Gerber V. Inflammatory airway disease of horses - revised consensus statement. J Vet Intern Med 2016;30:503-515.
  7. Hoffman AM, Mazan MR. Programme of lung function testing horses suspected with small airway disease. Equine Vet Edu 1999;11:322-328.
  8. Viel L. Significance of bronchoalveolar cytology in inflammatory airway disease. In:Hoffman A, Robinson NE, Wade JF, editors. Inflammatory Airway Disease: Defining the Syndrome. Havemeyer Foundation, Boston, USA. 2002:52-54.
  9. Couëtil LL, Hoffman AM, Hodgson J. Inflammatory airway disease of horses. J Vet Intern Med 2007;21:356-361.
  10. Hughes KJ, Nicolson L, Da Costa N. Evaluation of cytokine mRNA expression in bronchoalveolar lavage cells from horses with inflammatory airway disease. Vet Immunol Immunopathol 2011;140:82-89.
  11. Beekman L, Tohver T, Leguillette R. Comparison of cytokine mRNA expression in the bronchoalveolar lavage fluid of horses with inflammatory airway disease and bronchoalveolar lavage mastocytosis or neutrophilia using rest software analysis. J Vet Intern Med 2012;26:153-161.
  12. Secombe CJ, Lester GD, Robertson ID, Cullimore AM. Retrospective survey of bronchoalveolar lavage fluid cytology in western australian horses presented for evaluation of the respiratory tract: Effect of season on relative cell percentages. Aust Vet J 2015;93:152-156.
  13. Ivester KM, Couetil LL, Moore GE. Environmental exposures and airway inflammation in young thoroughbred horses. J Vet Intern Med 2014;28:918-924.
  14. Hansen S, Fjeldborg J, Hansen AJ, Baptiste KE. Reliability of cytological evaluation of mast cells from bronchoalveolar lavage fluid in horses: Intraobserver agreement and mast cell identification. Equine Vet Educ 2019.
    doi: 10.1111/eve13112google scholar: lookup
  15. Hoffman AM, Mazan MR, Ellenberg S. Association between bronchoalveolar lavage cytologic features and airway reactivity in horses with a history of exercise intolerance. Am J Vet Res 1998;59:176-181.
  16. Mazan MR, Hoffman AM. Effects of aerosolized albuterol on physiologic responses to exercise in Standardbreds. Am J Vet Res 2001;62:1812-1817.
  17. Bedenice D, Mazan MR, Hoffman AM. Association between cough and cytology of bronchoalveolar lavage fluid and pulmonary function in horses diagnosed with inflammatory airway disease. J Vet Intern Med 2008;22:1022-1028.
  18. Gerber V, Lindberg A, Berney C, Robinson NE. Airway mucus in recurrent airway obstruction-short term response to environmental challenge. J Vet Intern Med 2004;18:92-97.
  19. Hoffman AM. Bronchoalveolar lavage: Sampling technique and guidelines for cytologic preparation and interpretation. Vet Clin Equine 2008;24:423-435.
  20. Ambulatory Monitoring Inc. The Open Pleth™ system manual: version 3.3. New York,2010;1-60.
  21. Nolen-Walston RD, Boston RC, Wilkins PA. Temporal agreement of histamine bronchoprovocation testing in horses using open plethysmography. J Vet Intern Med 2008;22:823.
  22. Cullimore AM, Secombe CJ, Lester GD, Robertson ID. Bronchoalveolar lavage fluid cytology and airway hyper-reactivity in clinically normal horses. Aust Vet J 2018;96:291-296.
  23. Pacheco AP, Paradis MR, Hoffman AM. Age effects on blood gas, spirometry, airway reactivity, and bronchoalveolar lavage fluid cytology in clinically healthy horses. J Vet Intern Med 2014;28:603-608.
  24. Leuppi JD. Bronchoprovocation tests in asthma:direct vs indirect challenges. Curr Opin Pulm Med 2014;20:31-36.
  25. Secombe CJ, Lester GD, Robertson ID, Cullimore A. Pulmonary function testing, bronchoalveolar fluid cytology and mast cell tryptase in a group of Western Australian horses. J Vet Intern Med 2014;28:1125.
  26. Dacre KJ, Mcgorum BC, Marlin DJ. Organic dust exposure increases mast cell tryptase in bronchoalveolar lavage fluid and airway epithelium of heaves horses. Clin Exp Allergy 2007;37:1809-1818.
  27. Perkins GA, Viel L, Wagner B. Histamine bronchoprovocation does not affect bronchoalveolar lavage fluid cytology, gene expression and protein concentrations of IL-4, IL-8 and IFN-γ. Vet Immunol Immunopathol 2008;126:230-235.
  28. Couetil LL, Denicola DB. Blood gas, plasma lactate and bronchoalveolar lavage cytology analyses in racehorses with respiratory disease. Equine Vet J Suppl 1999;30:77-82.
  29. Richard EA, Fortier GD, Lekeux PM, Van Erck E. Laboratory findings in respiratory fluids of the poorly-performing horse. The Vet J 2010;185:115-122.
  30. Richard EA, Fortier GD, Pitel PH. Sub-clinical diseases affecting performance in standardbred trotters: Diagnostic methods and predictive parameters. Vet J 2010;184:282-289.
  31. Allen KJ, Tremaine WH, Franklin SH. Prevalence of inflammatory airway disease in national hunt horses referred for investigation of poor athletic performance. Equine Vet J Suppl 2006;36:529-534.
  32. Gerber V, Robinson NE, Luethi S. Airway inflammation and mucus in two age groups of asymptomatic well performing sport horses. Equine Vet J 2003;35:491-495.
  33. Depecker M, Richard EA, Pitel PH. Bronchoalveolar lavage fluid in standardbred racehorses: Influence of unilateral/bilateral profiles and cut off values on lower airway disease diagnosis. Vet J 2014;199:150-156.

Citations

This article has been cited 2 times.
  1. Davis KU, Sheats MK. Differential gene expression and Ingenuity Pathway Analysis of bronchoalveolar lavage cells from horses with mild/moderate neutrophilic or mastocytic inflammation on BAL cytology. Vet Immunol Immunopathol 2021 Apr;234:110195.
    doi: 10.1016/j.vetimm.2021.110195pubmed: 33588285google scholar: lookup
  2. Röschmann J, Naef J, Doras C, Gerber V. Respiratory Rate Recovery After Submaximal Lunging Exercise Is Delayed in Asthmatic Horses with Neutrophilic Airway Inflammation. Animals (Basel) 2025 Mar 2;15(5).
    doi: 10.3390/ani15050713pubmed: 40075996google scholar: lookup
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