Airway inflammation in feline asthma

December 20, 2011

Cocayne, C. G., C. R. Reinero, et al. (2011). “Subclinical airway inflammation despite high-dose oral corticosteroid therapy in cats with lower airway disease.” Journal of feline medicine & surgery 13(8): 558-563.

It is estimated that 1% of the pet cat population is affected by feline asthma and chronic bronchitis. Both conditions are chronic, diffuse inflammatory diseases of the lower airway that can lead to irreversible damage called airway remodeling. Bronchoalveolar lavage fluid (BALF) analysis is the only diagnostic test readily available in a clinical setting to determine the type of inflammatory cell present in the lower airways. There are no studies in cats that have determined if absence of clinical signs correlates with absence of airway inflammation. This study is a retrospective evaluation of 10 cats meeting criteria for inclusion in the study. The goal was to determine the correlation between the resolution of clinical signs in cats receiving oral glucocorticoids with the resolution of inflammation based on BALF cytology. The findings showed that 70% of the cats diagnosed with asthma or chronic bronchitis that had resolution of clinical signs (cough, wheeze, or episodic respiratory distress) with concurrent high-dose glucocorticoid therapy still had evidence of persistent airway inflammation based on BALF cytology. The results support the statement that caution should be used when equating absence of clinical signs with the absence of airway inflammation. Premature tapering of glucocorticoids based on absence of clinical signs in cats with subclinical inflammation could be detrimental in the long run. [VT]

Related articles:  
Leemans, J., N. Kirschvink, et al. (2011). “Effect of short-term oral and inhaled corticosteroids on airway inflammation and responsiveness in a feline acute asthma model.” Veterinary journal, in press.