Diagnostic utility and clinical application of imaging for pleural space infections

Timely diagnosis of pleural space infections and rapid initiation of effective pleural drainage for those patients with complicated parapneumonic effusions or empyema represent keystone principles for managing patients with pneumonia. Advances in chest imaging provide opportunities to detect parapneumonic effusions with high sensitivity in patients hospitalized for pneumonia and to guide interventional therapy. Standard radiographs retain their primary role for screening patients with pneumonia for the presence of an effusion to determine the need for thoracentesis. Ultrasonography and CT scanning, however, have greater sensitivity for fluid detection and provide additional information for determining the extent and nature of pleural infection. MRI and PET scan can image pleural disease, but their role in managing parapneumonic effusions is not yet clearly defined. Effective application of chest images for patients at risk for pleural infection, however, requires a comprehensive understanding of the unique features of each modality and relative value. This review presents the diagnostic usefulness and clinical application of chest imaging studies for evaluating and managing pleural space infections in patients hospitalized for pneumonia.