Spontaneous bacterial empyema in liver cirrhosis: an underdiagnosed pleural complication.

Spontaneous bacterial empyema, defined as spontaneous infection of the pleural fluid, represents a distinct complication of hepatic hydrothorax with a different pathogenesis, clinical course and treatment strategy from those of empyema secondary to pneumonia. Nearly 40% of episodes of spontaneous empyema are not associated with spontaneous bacterial peritonitis (SBP) or even ascites. The condition portends a poor prognosis, and is frequently under-diagnosed. This article reviews the pathogenesis, diagnosis and management of spontaneous bacterial empyema.