Approximately 50% of patients who are admitted to the hospital with community-acquired pneumonia will develop a pleural effusion.1–2
While most parapneumonic effusions will resolve without specific therapy, approximately 10% will become complicated or progress to empyema.3–
Because delays in the drainage of these clinically significant effusions have been associated with increased morbidity and mortality,4–
prompt detection and accurate characterization of a parapneumonic effusion are important. Guidelines5
based on a consensus conference have comprehensively summarized the literature regarding parapneumonic effusions and have made specific recommendations for their management. Although this document reflects the “state of the art,” as the authors noted, most studies of parapneumonic effusions have been observational, often with a limited numbers of patients.