- Also called thoracic empyema
- Purulent effusion in the pleural space
- Most significant in:
- Horses
- Usually secondary to pneumonia or lung abscesses
- Streptococci are most commonly isolated
- Usually yellow exudate
- Often triggered by stress of travelling, competition or similar
- Dogs
- Often results from migrating grass awns
- Actinomyces, Nocardia and Bacteroides spp. are the most frequently recovered organisms
- Usually blood stained viscous or creamy exudate, often bilateral
- Yellowish granules may be present within the exudate
- Thickened pleura, sometimes fibrinous
- Cats
- Pathogenesis is unclear, possible due to bite wounds or penetrated oesophagus
- P. multocida and other Gram-negative organisms are frequently recovered
- Usually creamy yellow or greyish brown exudate, often bilateral