Treatment of naturally occurring asthma with inhaled fluticasone or oral prednisolone: A randomized pilot trial.

The objective of this study was to compare inhaled glucocorticoids with oral glucocorticoids for treatment of naturally occurring feline asthma. Secondary goals were to evaluate serum allergy testing results in cats and to quantify the effect of an inhaled glucocorticoid (fluticasone) on glucose homeostasis. Nine cats with asthma were enrolled on the basis of clinical signs, thoracic radiographic findings, and airway eosinophilia. Cats were randomized and 4 cats were treated with oral glucocorticoids and 5 cats with inhaled glucocorticoids, with a 7-day course of oral glucocorticoids overlapping at the start of therapy. Cats were evaluated at baseline and at 8 wk with thoracic radiographs, bronchoalveolar lavage, lung function testing, and fructosamine levels. Serum allergen panels were evaluated. All cats were clinically normal after treatment and had significantly improved airway eosinophilia and decreased nucleated cell count. No improvement was seen in radiographic changes after treatment with either therapy. Oral, but not inhaled glucocorticoids, caused a decrease in airway resistance, although cats in the inhaled group had a higher baseline resistance than those in the oral group. Fructosamine levels did not change with treatment. Fifty percent of cats tested positive for immunoglobulin E (IgE) antibodies. Asthma is a heterogeneous condition; individual cats responded well to both oral and inhaled glucocorticoids. Ongoing evaluation of the potential underlying causes and therapeutic options is warranted with a larger group of cats.