Pleural Effusion-Cell Count Patterns

Pleural WBC Count >10k

  • Parapneumonic Effusion/Empyema (see [[Pleural Effusion-Parapneumonic]]): most common etiology of WBC >10k
  • Acute Pancreatitis (see [[Acute Pancreatitis]])
  • Acute PE (see [[Acute PE]])
  • Collagen Vascular Disease
  • Malignancy
  • Tuberculosis (see [[Tuberculosis]])

Neutrophil-Predominant Pleural Effusion

  • Parapneumonic Effusion/Empyema (see [[Pleural Effusion-Parapneumonic]])
  • Benign Asbestos Pleural Effusion (see [[Benign Asbestos Pleural Effusion]])
  • Paragonimiasis (see [[Paragonimiasis]])

Lymphocyte-Predominant Pleural Effusion

  • Tuberculosis (see [[Tuberculosis]])
  • Coccidioidomycosis (see [[Coccidioidomycosis]])

Pleural Fluid Eosinophilia

(defined as pleural eosinophils 10% or greater)
(number of eosinophils in pleural space is closely correlated with pleural IL-5 levels)

  • Blood: common etiology
    • Hemothorax (see [[Pleural Effusion-Hemothorax]]): pleural fluid eosinophilia typically appears later, during second week
    • Benign Asbestos Pleural Effusion (see [[Benign Asbestos Pleural Effusion]]): pleural eosinophilia is seen in 50% of cases
    • Acute PE (see [[Acute PE]]): typically when pleural fluid is bloody
  • Air: common etiology
    • Pneumothorax (see [[Pneumothorax]]): pleural eosinophils appear within 3 days and peak at day 6
  • Parasitic Infection:
    • Paragonimiasis (see [[Paragonimiasis]]): with accompanying PMN-predominance
    • Echinococcosis (see [[Echinococcosis]])
  • Drug-Induced Pleural Effusion:
    • Dantrolene (see [[Dantrolene]])
    • Isotretinoin (Accutane) (see [[Isotretinoin]])
    • Mesalamine (see [[Mesalamine]])
    • Nitrofurantoin (see [[Nitrofurantoin]])
    • Penicillins (see [[Penicillins]])
    • Propylthiouracil (PTU) (see [[Propylthiouracil]])
    • Sulfasalazine (see [[Sulfasalazine]])
  • Pulmonary Infiltrates with Eosinophilia:
    • Hypereosinophilic Syndrome (see [[Hypereosinophilic Syndrome]])
    • Churg-Strauss Syndrome (see [[Churg-Strauss Syndrome]])
    • Acute Eosinophilic Pneumonia (see [[Acute Eosinophilic Pneumonia]])
  • Other
    • Tuberculous Pleuritis (see [[Tuberculosis]]): with accompanying lymphocyte-predominance
    • Idiopathic Pleural Eosinophilia
    • Malignancy: occasionally associated with pleural eosinophilia
    • Parapneumonic Effusion (see [[Pleural Effusion-Parapneumonic]]): occasionally associated with pleural eosinophilia
    • Transudative Pleural Effusion (see [[Pleural Effusion-Transudate]]): some cases have been reported to be associated with pleural eosinophilia