Pleural diseases remain a common and challenging clinical problem. With an estimated 1.5 million new pleural effusions diagnosed annually in the United States, the incidence approaches that of diabetes (1.8 million new diagnoses annually) and eclipses that of congestive heart failure (400,000 new diagnoses annually). Spontaneous and iatrogenic pneumothoraces affect an additional 40,000.

Yet in spite of pleural diseases' high prevalence and standardized diagnostic approaches, the etiology of up to one-quarter of effusions remains unknown even after an exhaustive investigation. Almost 75 percent of effusions are ultimately due to congestive heart failure, malignancy or infection, and with an aging population, the incidence of all three continues to rise worldwide. This update addresses some of the latest understanding and approaches to management of malignant pleural disease and pleural space infection.