Evaluation of association of blood and bronchoalveolar eosinophil numbers and serum total immunoglobulin E concentration with the expression of nonspecific airway reactivity in dogs.

OBJECTIVE To characterize the relation between bronchoalveolar and blood eosinophil numbers, serum total IgE concentration, and nonspecific airway reactivity in healthy dogs. ANIMALS 26 healthy Beagles. PROCEDURE Prior to measurement of nonspecific airway responsiveness, dogs were anesthetized and bronchoscopy was performed to recover bronchoalveolar lavage (BAL) fluid. Repeated measurements were made in 6 dogs. RESULTS The percentage of blood eosinophils varied between 0 and 13 (mean +/- SD, 5.6 +/- 3.6) %, the percentage of eosinophils in BAL fluid ranged between 0 and 63.5 (8.8 +/- 12.9) %, and total serum IgE concentration was 0.1 to 107.5 (23.4 +/- 29.1) U/ml. A strong association was evident between numbers of blood eosinophils and total serum IgE concentration (R2 = 0.413, P < 0.001), and a trend toward an association between numbers of blood eosinophils and numbers of eosinophils in BAL fluid was apparent (R2 = 0.110, P < 0.053). Significant associations were not found between any other aspects of the blood and BAL fluid cell profiles and total serum IgE concentration or airway reactivity. Serum total IgE concentration was not associated with airway reactivity. Further, in dogs examined on repeated occasions, variation in BAL fluid eosinophil numbers was not associated with any change in serum total IgE concentration or airway reactivity. CONCLUSIONS Neither numbers of bronchoalveolar or blood eosinophils nor serum total IgE concentration have a significant role in determining airway reactivity in health dogs.