Presence of bronchial nodules, younger age, and heavier body weight are associated with a diagnosis of eosinophilic lung disease in dogs with cough.

Abstract

To describe the association between a diagnosis of eosinophilic lung disease (ELD) in dogs with signalment and bronchoscopic features and evaluate the accuracy of visualization of nodules for the diagnosis of ELD. 781 dogs with cough that underwent bronchoscopy between 2014 and 2016. Data were extracted from the medical records of each included dog. Multivariable logistic regression was performed to investigate associations between ELD and patient characteristics. ELD was diagnosed in 113 (14.5%) dogs. More than 3 nodular lesions of the bronchial mucosa were detected in 64 (8.2%) dogs. The odds of having ELD were greater in dogs with nodules (adjusted OR [aOR], 26.0; 95% CI, 13.0 to 52.0) and static bronchial collapse (aOR, 2.3; 95% CI, 1.1 to 4.6), and lower in dogs having focal versus diffuse inflammation (aOR, 0.05; 95% CI, 0.01 to 0.37). The odds of having ELD decreased for each 1-year increase in age (aOR, 0.86; 95% CI, 0.80 to 0.92), and increased for each 1-kg increase in weight (aOR, 1.04; 95% CI, 1.01 to 1.06). Visualization of nodules during bronchoscopy had a overall accuracy of 89.4% (95% CI, 87.0% to 91.4%), sensitivity of 41.6% (32.4% to 51.2%), and specificity of 97.5% (96.0% to 98.5%) for a diagnosis of ELD. On the basis of high specificity and negative predictive value, lack of visualization of bronchial nodules during bronchoscopy can be used to preliminarily rule out ELD. However, visualization of bronchial nodules does not imply presence of ELD. This could be especially relevant when results of BAL cytology are available several days after the actual bronchoscopy.