Abstract:
Two dogs had a 3 to 4 week history of persistent pyrexia, reduced exercise tolerance, inappetence
and coughing and failed to respond to repeated courses of antibiotics. Clinical examination detected
adventitious lung sounds, pyrexia and submandibular lymphadenopathy. Haematology in both dogs
revealed an inflammatory leukogram. Both dogs had radiological abnormalities consistent with a
multifocal interstitial lung pattern. Computed tomography performed in one dog had characteristic
changes of cryptogenic organising pneumonia (COP), an extremely rare idiopathic interstitial lung
disease. The abnormal pulmonary findings included several parenchymal bands, multifocal patchy
ground-glass opacities and multifocal subpleural and peribronchial hyperattenuating poorly defined
nodular opacities throughout the lungs. Bronchoalveolar lavage analysis in both dogs revealed a
sterile suppurative exudate, excluding eosinophilic bronchopneumopathy. There was rapid
resolution of clinical and radiological signs with corticosteroids and relapse in one dog after
discontinuation of steroids supporting the diagnosis of this rare condition. Lung biopsy, which was
not performed in either case, is definitive but considered invasive with major complications reported
including death.
