Light’s Criteria Versus Costa’s Criteria in Differentiating Transudative & Exudative Pleural Effusions

Introduction: Aim of this study is to compare COSTA’S and LIGHT’S criteria in identifying exudative from transudative pleural effusions.Materials & Methods: A prospective study that is hospital-based was conducted at GHCCD, during Jan ۲۰۱۷ to August ۲۰۱۸ in ۸۰ patients who presented with pleural effusion. Light’s and Costa’s criteria were applied to differentiate them into transudative and exudative effusions.Results: Among the pleural effusions, ۸۳.۷۵% were exudates and ۱۶.۲۵% were transudates. Tuberculous effusion (۴۵%) was the most common among exudates, and chronic kidney disease (۱۰%) was the most common among the transudates. On biochemical analysis of effusions, the mean pleural fluid cholesterol levels were ۷۴.۰۲±۲۰.۵۱mg/dl and ۲۹.۲۳±۷.۴۴mg/dl in exudative and transudative effusions respectively. On ROC analysis, the cut-off value for pleural fluid cholesterol was considered >۵۰mg/dl and <۲۹mg/dl for exudative and transudative effusions respectively. The mean pleural fluid LDH cut-off values on ROC analysis was >۲۳۱U/L for exudative effusions and <۲۳۱U/L for transudative effusions. The sensitivity, specificity, PPV, NPV of Lights criteria observed to be ۱۰۰%, ۶۱.۵%, ۹۳.۰۵% & ۱۰۰% with accuracy of ۹۳.۷۵% whereas the values of Costa’s criteria were ۹۷%, ۹۲%, ۹۸%, ۸۵.۷% with accuracy of ۹۶.۲۵% in differentiating exudates and transudates. P-value was statistically significant for both criteria.Conclusion: Pleural fluid LDH and cholesterol are found to be excellent parameters to differentiate transudates and exudates. Costa’s criteria is simple, convenient with almost equal sensitivity and more specificity in comparison to Light’s criteria, with fewer pleural fluid parameters compared to Light’s criteria.

Keywords:

Pleural fluid cholesterol , Costa’s criteria , Light’s criteria , Pleural Fluid LDH