light criteria for pleural effusion includes protein and LDH

  • Lights Criteria
    • Pleural protein >50% serum protein
    • Pleural LDH > 60% of serum LDH (from lysis of neutrophils)
    • Pleural LDH > 2/3 of upper limit of normal serum LDH
  • diuretic use will cause exudative effusion in heart failure patients
  • If no serum lab is available, one can also assume normal protein and LDH
    • Pleural protein > 2.9
    • Pleural LDH > 60% upper limit of normal
    • Pleural cholesterol > 45 mg/dL