A research study from Australia points to the potential to use exhaled to determine lower airway disease. The study was titled, "Exhaled breath condensate hydrogen peroxide, pH and leukotriene B4 are associated with lower airway inflammation and airway cytology in the horse" and was authored by Surita du Preez, S.L. Raidal, G.S. Doran, M. Prescott and K.J. Hughes
This prospective, cross‐sectional study by Surita du Preez and colleagues in Australia aimed to characterize associations between biomarkers in exhaled breath condensate (EBC) and the cytological and endoscopic findings in horses with lower airway inflammation.
Forty-seven horses were included in the study, 27 of which presented with respiratory disease and/or poor performance and 20 of which were asymptomatic. All horses underwent lower airway endoscopy and EBC analysis, with hydrogen peroxide (HO) concentration, pH, and the pro-inflammatory eicosanoid leukotriene B (LTB) being measured. During endoscopic examination, tracheal mucus was graded and a tracheal aspirate (TA) and bronchoalveolar lavage (BAL) performed. Multivariable linear regression was used to identify associations between biomarkers and lower airway disease.
EBC pH and HO concentrations were higher in horses with lower airway inflammation and were positively correlated with the percentage of neutrophils in the BAL fluid. Mast cell and eosinophil percentages in BAL fluid were negatively associated with EBC pH and positively associated with EBC LTB, respectively.
Bottom line: Exhaled breath condensate pH and HO concentrations are altered by inflammation and might offer a non-invasive method for diagnosing and monitoring lower airway inflammation in the future.
For more information on this research paper visit the Wiley Online Library.