A<unk>  is a type of pleural<unk>  that arises as a result of a pneumonia.  There are three types of<unk> s: uncomplicated<unk> s, complicated<unk> s, and empyema.  Uncomplicated<unk> s generally respond well to appropriate antibiotic treatment.  Complicated<unk> s respond more variably: many resolve with antibiotics but may benefit from early pleural fluid drainage.  Treatment of empyemas includes antibiotics, complete pleural fluid drainage, and reexpansion of the lung.
A<unk>  is any pleural<unk>  that is associated with a bacterial pneumonia, lung abscess or bronchiectasis.  40% of all patients with bacterial pneumonia develop a pleural<unk> , and the development of a pleural<unk>  increases morbidity and mortality as compared with an isolated pneumonia. .  In general<unk> s have 3 stages:
Exudative: Due to capillary leak, causing a sterile<unk>  that has a poly predominance, with normal glucose and pH.  It is seen within the 1st 72, and will usually resolve with antibiotics alone.
Fibrinopurulent: Occurs during days 3-7.  The pleural fluid becomes infected with bacteria, and the lactate dehydrogenase (LDH) rises, as the glucose and pH fall.  As the fibroblasts get busy, loculations develop which limits the extension of the empyema.
Organization: Further fibroblast activity produces a pleural peel leading to restrictive lung disease.  Without definitive treatment, the empyema can drain externally (empyema necessitatis) or into the lung to produce a broncho-pleural fistula.
Approximately 20% of all<unk> s evolve into empyema.  Hippocrates described empyema thoracis around 400 BC and predicted drainage of the pleural cavity as the treatment of choice.  The term empyema refers to either the presence of gross pus in the pleural space, or a positive gram stain on pleural fluid analysis.  60% of empyemas evolve from a<unk> , 20% after thoracic surgery and 20% from thoracic trauma, esophageal perforation, thoracentesis or subdiaphragmatic infection.  The majority of patients who develop empyema have underlying disease, most frequently alcoholism (especially in patients with anaerobic infections), malignancy and diabetes.
Exudative: Due to capillary leak, causing a sterile<unk>  that has a poly predominance, with normal glucose and pH.  It is seen within the 1st 72, and will usually resolve with antibiotics alone.
Fibrinopurulent: Occurs during days 3-7.  The pleural fluid becomes infected with bacteria, and the lactate dehydrogenase (LDH) rises, as the glucose and pH fall.  As the fibroblasts get busy, loculations develop which limits the extension of the empyema.
Organization: Further fibroblast activity produces a pleural peel leading to restrictive lung disease.  Without definitive treatment, the empyema can drain externally (empyema necessitatis) or into the lung to produce a broncho-pleural fistula.
Parapneumonic effusion
Trapped lung
Pleurisy
Round pneumonia
Pulmonary consolidation
Pleural effusion
Cavitary pneumonia
Hydropneumothorax