title: Collection of exhaled breath condensate and analysis of hydrogen peroxide as a potential marker of lower airway inflammation in cats.
abstract: The objective of this study was to describe a standardised and non-invasive method for exhaled breath condensate (EBC) collection in cats and to test whether determination of hydrogen peroxide (H(2)O(2)) in EBC might be used as marker of lower airway inflammation. The technique of barometric whole body plethysmography for cats was combined with a system to condense the effluent air from the plethysmograph, allowing simultaneous EBC collection and respiratory pattern measurement. H(2)O(2) was determined spectrophotometrically. Eighteen experimental cats were used to investigate the impact on EBC volume and EBC H(2)O(2) of plethysmograph ventilation rate, collection duration, sample stability, within-day and day-to-day variability. After determination of a standardised EBC collection procedure, correlation analyses between EBC H(2)O(2) and bronchoalveolar lavage (BAL) cytology of healthy and allergen-challenged Ascaris suum (AS)-sensitised cats were performed. A significant and positive correlation between EBC H(2)O(2) and bronchoalveolar lavage (BAL) neutrophil% was found in healthy cats (P < 0.001, r = 0.55), whereas in AS-sensitised cats, correlation with BAL eosinophil% was significant (P < 0.005, r = 0.61). H(2)O(2) was increased after an allergen challenge in AS-sensitised cats (n = 6, 0.56+/-0.12 versus 1.08+/-0.35 micromol/L, P < 0.05). This study proposes a non-invasive, well tolerated and repeatable method of EBC collection for cats and suggests that EBC H(2)O(2) might be used as non-invasive biomarker for monitoring lower airway inflammation.
authors.affiliation: Section of Pharmacology, Pharmacotherapy and Toxicology, Department of Functional Sciences B41, Faculty of Veterinary Medicine, University of Liège, 4000 Liège, Belgium. Nathalie.Kirschvink@ulg.ac.be
authors.forename: Nathalie
authors.initials: N
authors.lastname: Kirschvink
authors.forename: David
authors.initials: D
authors.lastname: Marlin
authors.forename: François
authors.initials: F
authors.lastname: Delvaux
authors.forename: Jérôme
authors.initials: J
authors.lastname: Leemans
authors.forename: Cécile
authors.initials: C
authors.lastname: Clercx
authors.forename: Andrew
authors.initials: A
authors.lastname: Sparkes
authors.forename: Pascal
authors.initials: P
authors.lastname: Gustin
mesh_terms: D000402:Airway Obstruction / Q000175:diagnosis / Q000662:veterinary*; D000818:Animals; D015415:Biomarkers / Q000032:analysis / Q000378:metabolism; D001944:Breath Tests / Q000379:methods*; D001992:Bronchoalveolar Lavage Fluid / Q000166:cytology; D001999:Bronchoscopy / Q000662:veterinary; D016022:Case-Control Studies; D002371:Cat Diseases / Q000175:diagnosis* / Q000473:pathology; D002415:Cats; D005260:Female; D006861:Hydrogen Peroxide / Q000032:analysis* / Q000378:metabolism; D008297:Male; D011237:Predictive Value of Tests
chemical_list: D015415:Biomarkers; D006861:Hydrogen Peroxide