Effect of inclusion or exclusion of epithelial cells in equine respiratory cytology analysis.

The study deals with an evaluation of the impact of inclusion or exclusion of epithelial cells in respiratory cytology analysis of horses, focusing particularly on samples from tracheal wash and bronchoalveolar lavage. Results suggest that their inclusion or exclusion can significantly alter the interpretation of airway inflammation.

Objectives and Method of the Study

• The purpose of the research was to ascertain whether including or excluding epithelial cells would influence the analysis and interpretation of respiratory cytology in horses.
• The research used differential cell counts from tracheal wash (TW) and bronchoalveolar lavage (BAL) cytology, two common techniques to sample cells in a horse’s respiratory system.
• The criteria for indicating airway inflammation were more than 20% neutrophils in the TW, more than 10% neutrophils in the BAL, and/or more than 5% mast cells in the BAL.

Findings of the Study

• The team found that there was a shift in classification from ‘normal’ to ‘abnormal’ when epithelial cells were not considered in differential counts.
• Specifically, 21% of the horses were reclassified under TW neutrophils, 4% under BAL neutrophils, and 8% under BAL mast cells when epithelial cells were excluded from the counts.

Recommendations and Implications

• Based on the findings, the study recommends that researchers in future equine respiratory studies should clearly state whether epithelial cells were included or left out in differential counts.
• They also suggested the need for a consensus on whether to include epithelial cells in cytology reporting because it alters the categorizations and could potentially lead to different treatment decisions.
• The implications of this research are significant as it can influence the diagnosis and treatment planning in cases of equine respiratory diseases.