Pleural Effusion Causes

1. See Also
   1. Pleural Effusion
   2. Thoracentesis
   3. Pleural Fluid Interpretation
2. Causes: Most Common
   1. Transudate
      1. Congestive Heart Failure
      2. Cirrhosis
   2. Exudate
      1. Pneumonia
      2. Cancer
      3. Pulmonary Embolism
      4. Viral respiratory infection
      5. Coronary Artery Bypass Graft (CABG) Surgery
   3. References
      1. Light (2002) N Engl J Med 346:1971-7
3. Causes: Transudate
   1. See Transudate Pleural Effusion Findings
   2. Congestive Heart Failure
   3. Pneumonia
   4. Nephrotic Syndrome or hypoalbuminemia
   5. Pulmonary Atelectasis
   6. Peritoneal dialysis
   7. Constrictive Pericarditis
   8. Obstruction of superior vena cava
4. Causes: Exudate
   1. See Exudate Pleural Effusion Findings
   2. Pulmonary Embolism
   3. Parapneumonic Effusion (Pneumonia with effusion)
      1. Bacterial Pneumonia
      2. Mycobacterium tuberculosis
   4. Malignancy
      1. Lung Cancer (36%)
      2. Breast Cancer (25%)
      3. Lymphoma (10%)
      4. Primary pleural malignancy
   5. Dressler's Syndrome
      1. Post-Myocardial Infarction
      2. Post-Cardiotomy
   6. Gastrointestinal Disease
      1. Esophageal Perforation
      2. Pancreatitis
   7. Intraabdominal abscess
   8. Medications
      1. Methotrexate
      2. Nitrofurantoin
      3. Dantrolene sodium
      4. Methysergide
      5. Procarbazine
      6. Drug-induced Lupus related medications
         1. Procainamide
         2. Hydralazine
         3. Quinidine
5. Causes: Grossly Bloody Effusion (>100,000 cells/cu mm)
   1. See Bloody Pleural Effusion Findings
   2. Trauma (including recent chest surgery)
   3. Pulmonary Embolism
   4. Malignancy
   5. Pneumonia
6. Causes: Empyema (pus collection, Bronchopleural Fistula)
   1. See Empyema Pleural Effusion Findings
   2. Infection
      1. Pneumonia (50% of empyema causes)
      2. Abscess
         1. Lung Abscess
         2. Subphrenic abscess
      3. Mycobacterium tuberculosis
      4. Fungal infections
   3. Chest trauma (especially penetrating chest wounds)
   4. Spontaneous Pneumothorax
7. Causes: Other findings
   1. Lymphocytosis
      1. Cancer
      2. Lymphoma (esp. if >90%)
      3. Mycobacterium tuberculosis (esp. if >90%)
      4. Pulmonary Embolism
   2. Loculated Effusion
      1. Empyema
      2. Hemothorax
      3. Tuberculosis
   3. Massive pulmonary effusion
      1. Cancer (represents >50% of cases)
      2. Empyema
      3. Mycobacterium tuberculosis
8. References
   1. Light (2002) N Engl J Med 346:1971-7
   2. Medford (2005) Postgrad Med J 81 (961):702-10
   3. Porcel (2006) Am Fam Physician 73:1211-20
   4. Rabman (2005) Br Med Bull 72:31-47