Abstract
Objective: To study two alternative criteria to differentiate between exudates and transudates:a) pleural fluid cholesterol and b)the ratio of pleural fluid cholesterol to serum cholesterol in order to compare their diagnostic value with the widely accepted and used Light's criteria.
Method: 97 patients with pleural effusion were tested. According to Light's criteria there were 29 transudative and 68 exudative pleural effusions. Pleural fluid and serum levels of lactate dehydrogenase, protein and cholesterol were measured using colorimetric methods and a biochemical analyzer.
Results: Using as a cut-off value for the pleural fluid cholesterol the value of 65mg% (the upper limit to identify a pleural effusion as a transudate) this criterion yielded a sensitivity of 87% and a specificity of 79%. Using the alternative criterion of pleural fluid cholesterol to serum cholesterol ratio (and a cut-off level of 0,4 as the upper limit to identify a transudate) the sensitivity was 87% and the specificity was even greater at 81%.
Conclusions: This study showed that using pleural fluid cholesterol and pleural fluid cholesterol/serum cholesterol ratio may be useful for the differential diagnosis between transudates and exudates, and can provide assistance especially where other criteria are marginal or ambiguous.
- © 2011 ERS
