Curated insights • How it Works • Practical Pearls • Evidence Base
| Transudates |
| Exudates |
Validated in >7,000 patients (Porcel et al., 2026). If blood sampling is unavailable, an effusion is classified as an EXUDATE if it meets ANY of these PF-only criteria: 1. PF Protein > 3 g/dL 2. PF LDH > 250 IU/L 3. PF Cholesterol > 55 mg/dL
Light's Criteria: Any 1 positive = Exudate (Sensitivity 98%, Specificity ~71%). Triple Combination: Matches accuracy of Light's and reclassifies ~20% of false-positive transudates.
Diuretics in CHF patients can 'concentrate' pleural fluid, causing a transudate to meet exudative criteria (pseudo-exudate).
Revisiting Light's criteria: a validated blood-free triple combination matches diagnostic accuracy in over 7000 patients.
Effects of Light’s criteria on the diagnostic accuracy of pleural fluid carcinoembryonic antigen concentrations for malignant pleural effusion.
Pleural effusions: the diagnostic separation of transudates and exudates.
Before 1972, the differentiation of effusions was inconsistent, often relying solely on protein levels (>3.0 g/dL). Dr. Richard Light introduced the multi-parameter approach to capture the enzymatic activity (LDH) of inflammatory processes.
Curated insights • How it Works • Practical Pearls • Evidence Base
| Transudates |
| Exudates |
Validated in >7,000 patients (Porcel et al., 2026). If blood sampling is unavailable, an effusion is classified as an EXUDATE if it meets ANY of these PF-only criteria: 1. PF Protein > 3 g/dL 2. PF LDH > 250 IU/L 3. PF Cholesterol > 55 mg/dL
Light's Criteria: Any 1 positive = Exudate (Sensitivity 98%, Specificity ~71%). Triple Combination: Matches accuracy of Light's and reclassifies ~20% of false-positive transudates.
Diuretics in CHF patients can 'concentrate' pleural fluid, causing a transudate to meet exudative criteria (pseudo-exudate).
Revisiting Light's criteria: a validated blood-free triple combination matches diagnostic accuracy in over 7000 patients.
Effects of Light’s criteria on the diagnostic accuracy of pleural fluid carcinoembryonic antigen concentrations for malignant pleural effusion.
Pleural effusions: the diagnostic separation of transudates and exudates.
Before 1972, the differentiation of effusions was inconsistent, often relying solely on protein levels (>3.0 g/dL). Dr. Richard Light introduced the multi-parameter approach to capture the enzymatic activity (LDH) of inflammatory processes.
