accurate assessment of the size of the effusion and, where necessary, loculations using ultrasound or CT scanning
early diagnostic pleural aspiration, to assess fluid appearance, bacteriology and biochemistry
antibiotic therapy - depends on the bacteriology of the aspirated fluid; often requires metronidazole because organisms may not be revealed by culture
pleural fluid is drained - if this is not possible then surgery is indicated (surgical evacuation and lung decortication so that it may be fully expanded and so obliterate the pleural space)
intrapleural fibrinolytic therapy - a systematic review stated " with complicated infective pleural effusion or empyema, intrapleural fibrinolytic therapy was associated with a reduction in the requirement for surgical intervention and overall treatment failure but with no evidence of change in mortality" (2)
consider the possibility of tuberculosis
Drug and Therapeutics Bulletin 2006; 44 (3): 17-20.