The utility of soluble L-selectin measurements in the diagnostic evaluation of pleural effusions

Purpose: The analysis of pleural fluid is instrumental in the diagnostic evaluation of pleural effusions. Several parameters have been evaluated and diagnostic algorithms devised. Soluble L-selectin (sL-selectin) is a component in the regulation of leukocyte migration. As such, monitoring of these levels may improve our diagnostic abilities. This data will help to characterize sL-selectin in pleural fluid and to determine if the measurement of levels is of benefit in the separation of transudates and exudates. Methods: All patients undergoing diagnostic thoracentesis were eligible for study entry. Samples of pleural fluid and serum were obtained at the time of diagnostic thoracentesis. All labs, except sL-selectin assays, were done in the main hospital laboratory. The latter samples were processed separately and simultaneously run, via a quantitative sandwich enzyme immunoassay technique (R&D Systems, Minneapolis, MN, USA). Values were then statistically analyzed to learn if any significant differences existed between groups, i.e., transudates[mdit] vs. exudates. Results: Mean sL-selectin values ± standard deviation (ng/ml) Conclusions: This data displays a significant difference in the pleural fluid sL-selectin values when comparing translates to exudates, both by clinical and Light's criteria. Also, no difference between serum values for any group were found. Clinical Implications: Measurement of sL-selectin values may facilitate the classification of pleural effusions. (n = 40) Transdate Exudate Clinical - Pleural 269.2+/-114.6 409.1+/-156.8* Clinical - Serum 811.7+/-10.9 736.8+/-35.9 Light's - Pleural 258.9+/-96.3 396.4+/-171.0* Light's - Serum 789.7+/-309.8 793.0+/-358.4.