Pyogranulomatous pleuritis with empyema in hunting dogs.

Nine hunting breed dogs were treated for thoracic empyema of undetermined origin. Seven dogs returned to normal health after combined pleural drainage by modified Seldinger technique and long-term chemotherapy. Two were destroyed in the early phase of treatment. One died and one was destroyed due to recurrence. Associated signs in four of the dogs included thoracic wall swellings. In two of these, very small foreign bodies of plant origin were found intrathoracically at surgery. Predominantly anaerobic commensals of the mucous membranes were isolated from pleural exudate. Post-mortem examination in the four cases showed productive, pyogranulomatous intrathoracic inflammation and pleural adhesions. It is proposed that inhaled small plant parts, by synergism with endogenous microorganisms of mucous membrane origin, may be of aetiologic importance in seemingly idiopathic pyogranulomatous pleuritis with empyema in hunting dogs.