ABSTRACT
I. Introduction Empyema thoracis develops when bacteria enters the sterile pleural space and overwhelms the normal pleural defense mechanisms. The most common mode of entry for these bacteria is migration across the visceral pleura from an area of pneumonia. Bacteria may also enter the pleural space from a thoracic surgical procedure or after the development of a bronchopleural fistula (BPF). Empyema can occur from extension across the diaphragm of a subphrenic abscess or with esophageal perforation. Identifying and correcting the underlying etiology of the empyema is critical to successful treatment.
