Bronchoalveolar Lavage Cytology in Severe Equine Asthma: Cytocentrifugated Versus Sediment Smear Preparations

Overview

Journal Vet Sci

Publisher MDPI

Specialty Veterinary Medicine

Date 2023 Aug 25

PMID 37624314

Authors

Maria Morini

Francesca Gobbo

Riccardo Rinnovati

Noemi Romagnoli

Angelo Peli

Chiara Massarenti

Alessandro Spadari

Marco Pietra

Affiliations

Soon will be listed here.

Abstract

Equine asthma is a common respiratory disease that may affect horses of any age. The diagnosis of severe equine asthma (SEA) (historically referred as recurrent airway obstruction or RAO) is based mainly on the history of the animal and clinical signs, which are further supported by the cytological examination of the bronchoalveolar lavage (BAL). This can also be helpful in monitoring the inflammation of the lower airways in response to environmental management and medication. The cytocentrifugated preparation is usually considered the method of choice for BAL cytological interpretation. The aim of this study was to compare the results in terms of differential cell counts (DCC) in BAL cytology performed on sedimented smears and cytocentrifugated preparations. To carry this out, 48 BAL samples were collected from six horses with SEA that were subjected to a process of exacerbation of the disease by environmental stimuli, which was later followed by the appropriate treatment. Each collected BAL fluid was equally divided into duplicate portions: one processed by cytocentrifugation and one by sediment smear from simple centrifugation. Cytologic examination of all BAL by both methods showed poor concordance in DCC, although it was still able to allow diagnostic recognition of severe lung neutrophilic disorders. These results suggest that sediment smear preparation, although remaining a useful method in general equine practice associated with clinical assessments in the diagnosis of SEA under conditions where there is no possibility of using a cytocentrifuge, cannot be considered a comparable alternative.

Citing Articles

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References

Fogarty U, Buckley T . Bronchoalveolar lavage findings in horses with exercise intolerance. Equine Vet J. 1991; 23(6):434-7. DOI: 10.1111/j.2042-3306.1991.tb03756.x. View

Tee S, Dart A, MacDonald M, Perkins N, Horadagoda N, Jeffcott L . Effects of collecting serial tracheal aspirate and bronchoalveolar lavage samples on the cytological findings of subsequent fluid samples in healthy Standardbred horses. Aust Vet J. 2012; 90(7):247-51. DOI: 10.1111/j.1751-0813.2012.00950.x. View

Hoffman A . Bronchoalveolar lavage: sampling technique and guidelines for cytologic preparation and interpretation. Vet Clin North Am Equine Pract. 2008; 24(2):423-35, vii-viii. DOI: 10.1016/j.cveq.2008.04.003. View

Lapointe J, Vrins A, Lavoie J . Effects of centrifugation and specimen preparation technique on bronchoalveolar lavage analysis in horses. Equine Vet J. 1994; 26(3):227-9. DOI: 10.1111/j.2042-3306.1994.tb04374.x. View

Sweeney C, Rossier Y, Ziemer E, Lindborg S . Effects of lung site and fluid volume on results of bronchoalveolar lavage fluid analysis in horses. Am J Vet Res. 1992; 53(8):1376-9. View

Morini M, Peli A, Rinnovati R, Magazzu G, Romagnoli N, Spadari A . Immunohistochemical Expression of Neurokinin-A and Interleukin-8 in the Bronchial Epithelium of Horses with Severe Equine Asthma Syndrome during Asymptomatic, Exacerbation, and Remission Phase. Animals (Basel). 2021; 11(5). PMC: 8151432. DOI: 10.3390/ani11051376. View

Pickles K, Pirie R, Rhind S, Dixon P, Mcgorum B . Cytological analysis of equine bronchoalveolar lavage fluid. Part 1: Comparison of sequential and pooled aliquots. Equine Vet J. 2002; 34(3):288-91. DOI: 10.2746/042516402776186137. View

Pickles K, Pirie R, Rhind S, Dixon P, Mcgorum B . Cytological analysis of equine bronchoalveolar lavage fluid. Part 2: Comparison of smear and cytocentrifuged preparations. Equine Vet J. 2002; 34(3):292-6. DOI: 10.2746/042516402776186155. View

Bond S, Leguillette R, Richard E, Couetil L, Lavoie J, Martin J . Equine asthma: Integrative biologic relevance of a recently proposed nomenclature. J Vet Intern Med. 2018; 32(6):2088-2098. PMC: 6271326. DOI: 10.1111/jvim.15302. View

10.

Hughes K, Nicolson L, da Costa N, Franklin S, Allen K, Dunham S . Evaluation of cytokine mRNA expression in bronchoalveolar lavage cells from horses with inflammatory airway disease. Vet Immunol Immunopathol. 2011; 140(1-2):82-9. DOI: 10.1016/j.vetimm.2010.11.018. View

11.

Bedenice D, Mazan M, Hoffman A . 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(4):1022-8. DOI: 10.1111/j.1939-1676.2008.0109.x. View

12.

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. 2011; 26(1):153-61. DOI: 10.1111/j.1939-1676.2011.00847.x. View

13.

Mcgorum B, Dixon P, Halliwell R, Irving P . Comparison of cellular and molecular components of bronchoalveolar lavage fluid harvested from different segments of the equine lung. Res Vet Sci. 1993; 55(1):57-9. DOI: 10.1016/0034-5288(93)90034-d. View

14.

Couetil L, Thompson C . Airway Diagnostics: Bronchoalveolar Lavage, Tracheal Wash, and Pleural Fluid. Vet Clin North Am Equine Pract. 2020; 36(1):87-103. DOI: 10.1016/j.cveq.2019.12.006. View

15.

Mcgorum B, Dixon P . Evaluation of local endobronchial antigen challenges in the investigation of equine chronic obstructive pulmonary disease. Equine Vet J. 1993; 25(4):269-72. DOI: 10.1111/j.2042-3306.1993.tb02961.x. View

16.

Davis K, Sheats M . Bronchoalveolar Lavage Cytology Characteristics and Seasonal Changes in a Herd of Pastured Teaching Horses. Front Vet Sci. 2019; 6:74. PMC: 6426765. DOI: 10.3389/fvets.2019.00074. View

17.

Allen K, Tennant K, Franklin S . Effect of inclusion or exclusion of epithelial cells in equine respiratory cytology analysis. Vet J. 2019; 254:105405. DOI: 10.1016/j.tvjl.2019.105405. View

18.

Hermange T, Le Corre S, Bizon C, Richard E, Courouce A . Bronchoalveolar lavage fluid from both lungs in horses: Diagnostic reliability of cytology from pooled samples. Vet J. 2019; 244:28-33. DOI: 10.1016/j.tvjl.2018.12.002. View

19.

Couetil L, Cardwell J, Gerber V, Lavoie J, Leguillette R, Richard E . Inflammatory Airway Disease of Horses--Revised Consensus Statement. J Vet Intern Med. 2016; 30(2):503-15. PMC: 4913592. DOI: 10.1111/jvim.13824. View

20.

Mair T, Stokes C, Bourne F . Cellular content of secretions obtained by lavage from different levels of the equine respiratory tract. Equine Vet J. 1987; 19(5):458-62. DOI: 10.1111/j.2042-3306.1987.tb02644.x. View