Criteria for diagnosis of empyema - at least one of the following findings:
(1) organisms seen on smear of pleural fluid
(2) organisms seen on smear of pleural fluid
(3) empyema seen during surgery
(4) empyema seen on histopathologic examination
Criteria for diagnosis of lung abscess - at least one of the following findings:
(1) organisms seen on smear of lung cavity fluid
(2) organisms isolated in culture of lung cavity fluid
(3) lung abscess seen during surgery
(4) lung abscess seen on histopathologic examination
(5) abscess cavity seen on radiographic examination of lung
