Differential diagnosis of pleural effusion
| Diagnosis | Risk factors | Clinical presentation | Physical examination findings | Laboratory and imaging characteristics | Alternative diagnosis |
|---|---|---|---|---|---|
| Decompensated heart failure | History of ischemic or nonischemic cardiomyopathy, heart failure | Exertional dyspnea, dyspnea at rest, orthopnea, PND | Elevated JVD, pedal edema, crackles on lung auscultation | Transudative pleural effusion; usually bilateral simple pleural effusion | Lack of prior diagnosis of heart failure, orthopnea, PND |
| Malignancy (solid-organ or hematopoietic) | Known malignancy of lungs, metastasis to the lung | B symptoms (fatigue, weight loss, anorexia, night sweats, chills, fevers) | Lymph node enlargement | Exudative effusion; unilateral simple pleural effusion | Lack of personal or family history of malignancy; lack of risk factors such as smoking |
| Infection | Immunocompromised status | Fever, chills, productive cough, sweating | Bronchial breaths sound on auscultation | Exudative effusion; consolidation associated with parapneumonic effusion; loculated effusion; empyema; ground-glass opacities or lobular consolidation on chest CT | Symptoms for a few weeks, no documented fevers |
| Pulmonary embolism | History of venous thromboembolism, active malignancy, hypercoagulable state | Pleuritic chest pain | Sinus tachycardia | Exudative effusion; normal chest radiograph; filling defect on chest CT with contrast; may be associated with small pleural effusion | No known risk factors for venous thromboembolism; large pleural effusion |
| Lymphangioleiomyomatosis | Young females in reproductive age group | Chronic dyspnea, fatigue, spontaneous pneumothorax, pleural effusions | Associated with axillary and mediastinal lymphadenopathy | Chylous, exudative pleural effusion; cystic lung disease; ground-glass opacities and septal thickening on chest CT; renal angiomyolipoma | Lack of history of spontaneous pneumothorax |
| Cirrhosis | Alcoholic or nonalcoholic liver disease | Jaundice, ascites, fatigue, weight loss | Fluid thrill, shifting dullness on abdominal examination | Transudative pleural effusion; cirrhotic morphology of liver, ascites | Lack of history, risk factors for liver disease |
| Chylothorax | History of thoracic surgery, trauma, congenital disorders | Dyspnea, fatigue, yellow nails | Decreased breath sounds at site of pleural effusion, lymphadenopathy | Chylous pleural effusion; unilateral pleural effusion | Lack of thoracic duct injury due to surgery, trauma |
CT = computed tomography; JVD = jugular venous distention; PND = paroxysmal nocturnal dyspnea