RESUMO
Complicated parapneumonic effusion is one in which an invasive procedure is necessary for its resolution and empyema means pus in the pleural space. An early diagnosis and therapy of these conditions results in less morbidity and mortality. CT of the chest is important to study complex pleural effusions. Loculated effusions, those occupying more than 50% of the thorax, or which show positive Gram stain or bacterial culture, or a purulent effusion with a pH below 7.20, with a glucose level below 60 mg/dl or a LDH level more than three times the upper limit of normal for serum, are indications for an invasive procedure. These characteristics result from the evolution of a not well treated parapneumonic effusion, through the three stages: (1) exsudative; (2) fibrinopurulent; (3) fibrotic. Depending on the stage therapeutic methods vary from therapeutic thoracentesis, insertion of a chest tube with or without instillation of fibrinolytics, video-assisted thoracoscopic surgery, and lung decortication. A review of all these aspects are done based on a series of three cases reports with very different clinical presentation: one patient with empyema by Streptococcus pyogenes and that died rapidly due to massive hemoptysis; a patient with empyema due to acute pneumonia developing during an airflight; a patient with empyema and bacteraemia by Streptococcus pneumonia leading to the diagnosis of an unknown HIV infection.
