Evaluation of a guarded bronchoscopic method for microbial sampling of the lower airways in foals.
Abstract: A novel method to reduce contamination of the bronchoscope during microbial sampling of the lower airways of foals was evaluated. Methylene blue (MB) was used as a nasopharyngeal dye marker to assess the relative contamination from the upper airways of bronchoalveolar lavage (BAL) specimens obtained by standard bronchoscopy (SB) and a "guarded" bronchoscopic method (GB). For GB, a clear sterile cellulose sheath was fitted over the bronchoscope in an effort to protect the endoscope tip and channel from contamination. Methylene blue was detected visually in seven of eight BAL samples from foals following SB, but in none of the samples recovered by GB (p less than 0.001). Significantly less MB was detected in BAL by spectrophotometry in the GB group as well (p less than 0.02). The GB was next employed to study the microbial flora in the lower airways of healthy weaned foals (n = 30). Bacteria were isolated from 29 of 30 (97%) BAL samples, and in moderate or large numbers from 26 of 30 (87%) of the foals. Potential pathogens, including Bordetella bronchiseptica, Streptococcus zooepidemicus, Staphylococcus aureus, Mycoplasma felis and Streptococcus pneumoniae, were cultured from the lower airways of foals. In conclusion, the bronchoscope and bronchoalveolar lavage specimens were readily contaminated by a dye marker placed in the nasopharynx of foals, and the degree of contamination was significantly reduced by sheathing the endoscope. This contamination during bronchoscopy may obscure the interpretation of isolates from BAL specimens from foals, which may possess a bacterial flora in the lower airways without cytological evidence of inflammation.
Publication Date: 1991-10-01 PubMed ID: 1790487PubMed Central: PMC1263478
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- Comparative Study
- Journal Article
- Research Support
- Non-U.S. Gov't
Summary
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This research examines a new method of reducing contamination during bronchoscope microbial sampling within the lower airways of foals. Conducted via the use of methylene blue as a nasopharyngeal dye marker, the study suggests a contaminated bronchoscope may cause problems in the interpretation of isolates from bronchoalveolar lavage (BAL) specimens from foals. The tested “guarded” bronchoscope method, which involves a clear sterile sheath, showed a significant reduction in contamination.
Methodology
- The research made use of a specific dye marker, methylene blue (MB), to examine relative contaminations from the upper airways of BAL specimens. This was applied during both standard bronchoscopy (SB) and guarded bronchoscopy (GB).
- In the GB method, a clear sterile cellulose sheath was fitted over the bronchoscope with the aim of shielding the endoscope tip and channel from contamination.
- The presence of methylene blue, a sign of contamination, was visually assessed in the BAL specimens obtained from foal subjects.
Results
- The results showcased the presence of methylene blue in seven out of eight BAL samples taken from the foals following the standard bronchoscopy however, there was no detection of MB in any samples retrieved via the guarded method.
- Statistically, this difference was significant, with the GB method experiencing less contamination as evidenced by less detectable amounts of MB.
- The guarded bronchoscopy was further used to examine the microbial flora of the lower airways in healthy weaned foals.
- Bacteria were isolated in 97% of the BAL samples, and in moderate or large quantities in 87% of the foals. These included potential pathogens like Bordetella bronchiseptica, Streptococcus zooepidemicus, Staphylococcus aureus, Mycoplasma felis and Streptococcus pneumoniae.
Conclusion
- The research paper concludes that a bronchoscope and bronchoalveolar lavage samples could be readily contaminated by a dye marker located in the nasopharynx of foals.
- Within the study, containment was significantly reduced by sheathing the endoscope, suggesting that the Guarded Bronchoscopy method might offer a more accurate procedure, less prone to contamination.
- The researchers also suggest that this contamination during bronchoscopy could obscure the interpretation of isolates from BAL specimens from foals, which may have a bacterial flora in the lower airways without cytological evidence of inflammation.
Cite This Article
APA
Hoffman AM, Viel L, Muckle CA, Tesarowski DB.
(1991).
Evaluation of a guarded bronchoscopic method for microbial sampling of the lower airways in foals.
Can J Vet Res, 55(4), 325-331.
Publication
Researcher Affiliations
- Department of Clinical Studies, Ontario Veterinary College, University of Guelph, Ontario.
MeSH Terms
- Animals
- Bacteria / isolation & purification
- Bronchoalveolar Lavage Fluid / microbiology
- Bronchoscopy / veterinary
- Evaluation Studies as Topic
- Horses / microbiology
- Methylene Blue
References
This article includes 23 references
- J Lab Clin Med. 1974 Oct;84(4):559-73
- Am Rev Respir Dis. 1976 Jul;114(1):73-8
- Lung. 1989;167(5):261-7
- Equine Vet J. 1989 Jan;21(1):23-6
- Can J Vet Res. 1988 Apr;52(2):239-48
- Am Rev Respir Dis. 1988 Feb;137(2):259-64
- Am Rev Respir Dis. 1984 Nov;130(5):924-9
- Am Rev Respir Dis. 1987 Jan;135(1):250-63
- J Infect Dis. 1987 May;155(5):862-9
- J Infect Dis. 1987 May;155(5):855-61
- Am J Vet Res. 1985 Dec;46(12):2562-5
- Zentralbl Veterinarmed A. 1990 Jun;37(5):392-9
- Am Rev Respir Dis. 1990 Jul;142(1):238-57
- Am J Vet Res. 1984 May;45(5):898-902
- Am Rev Respir Dis. 1983 Aug;128(2):266-70
- J Am Vet Med Assoc. 1983 Jun 15;182(12):1374-6
- Am Rev Respir Dis. 1979 Mar;119(3):337-43
- Am Rev Respir Dis. 1977 Jul;116(1):41-7
- Zentralbl Veterinarmed B. 1979 Nov;26(9):722-8
- J Infect Dis. 1976 Nov;134(5):428-35
- J Am Vet Med Assoc. 1976 Sep 15;169(6):631-3
- Am Rev Respir Dis. 1975 Jul;112(1):59-64
- Vet Rec. 1965 May 29;77:632-3
Citations
This article has been cited 2 times.- Soliman R, Yousef M, Gelil SA, Aboul-Ella H. Development of novel Streptococcus equi vaccines with an assessment of their immunizing potentials and protective efficacies. BMC Vet Res 2024 May 3;20(1):173.
- Payette F, Charlebois A, Fairbrother JH, Beauchamp G, Leclere M. Nicoletella semolina in the airways of healthy horses and horses with severe asthma. J Vet Intern Med 2021 May;35(3):1612-1619.
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