Clinical, Bronchoscopic, Histopathologic, Diagnostic Imaging, and Arterial Oxygenation Findings in West Highland White Terriers with Idiopathic Pulmonary Fibrosis

摘要

BackgroundIdiopathic pulmonary fibrosis (IPF) is a chronic, interstitial lung disease primarily affecting West Highland White Terriers (WHWTs).ObjectiveTo describe the clinicopathological and diagnostic imaging features in WHWTs with IPF.AnimalsTwelve WHWTs with IPF and 14 healthy control WHWTs.MethodProspective study. Clinical signs and findings of physical examination, blood and arterial blood gas analyses, radiography, high-resolution computed tomography (HRCT), bronchoscopy and bronchoalveolar lavage (BAL) of IPF dogs were obtained and compared with controls. Histopathologic changes in IPF dogs were evaluated.ResultsMean partial pressure of oxygen was significantly lower in IPF (mean +/- SD, 65.5 +/- 15.4 mmHg) than in controls (99.1 +/- 7.8 mmHg, P <.001). The alveolar-arterial oxygen gradient was significantly higher in IPF (50.1 +/- 17.3 mmHg) than in controls (17.5 +/- 4.9 mmHg, P <.001). In HRCT, ground glass opacity (GGO) was detected in all IPF dogs, traction bronchiectasis in 4, and honeycombing in 1. Bronchoscopic airway changes were noted in all IPF dogs. On BAL fluid (BALF) cytology, the total cell count (TCC) was higher in IPF dogs, and the numbers but not the percentages of macrophages, neutrophils, and mast cells were increased. On histopathology, multifocal or diffuse interstitial fibrosis, type II pneumocyte hyperplasia, prominent intraalveolar macrophages, distortion of alveolar architecture, and emphysematous change were detected.Conclusion and Clinical ImportanceIPF causes substantial hypoxemia. In HRCT, GGO is a consistent finding. IPF dogs have concurrent airway changes and an increase in BALF TCC.