Units: US SI

Light’s Criteria for Exudative Effusions

Pleural Fluid Protein
Serum Protein
 
Pleural Fluid LDH
Serum LDH units/L
Serum LDH Upper Limit Normal
 

Light's Criteria: Exudative Effusions will have at least one of the following:

  • Pleural fluid protein / Serum protein >0.5
  • Pleural fluid LDH / Serum LDH >0.6
  • Pleural fluid LDH > 2/3 * Serum LDH Upper Limit of Normal

Note: While Light's Criteria are reported to be highly sensitive for exudative effusions, their specificity for exudative effusions is only 83%.

Equations

Scores