European Journal of Biomedical and Pharmaceutical Sciences

PLEURAL FLUID CHOLESTEROL IN EXUDATIVE AND TRANSUDATIVE PLEURAL EFFUSION

Dr. Kali Gandhi and Dr. Priyanka Agrawal*

ABSTRACT

Background: Light’s criteria is the gold standard to differentiate transudative pleural effusion from exudative pleural effusion, but it requires four biochemical estimations which in developing countries such as India, may not be feasible in every patient due to economic constraints. Also it is found that 25% of patients with transudates pleural effusion are mistakenly identified as having exudative effusion by Light's criteria. Pleural fluid cholesterol can be used to classify exudates and transudates as it misclassifies fewer cases than any other Light's parameters. Materials and methods: In this prospective study, 60 patients with pleural effusion were included. Pleural fluid total protein, LDH and cholesterol, serum total protein and LDH levels along with other investigations were studied. Clinical classification of transudate or exudate was done based on aetiology. Results: Based on clinical signs and symptoms, chest radiograph and other investigations, 52 of these effusions were classified as exudates and 8 as transudates. Using the pleural fluid cholesterol cut-off point >45 mg/dL to differentiate exudates and transudates, the sensitivity, specificity, positive predictive value (PPV) and the negative predictive value (NPV) were found to be 100%. Using Light’s criteria to differentiate exudates and transudates, the sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were found to be 98%, 87.5%, 98% and 87.5% respectively. The differences resulted from misclassification of 1 expected exudate as transudate out of 52 and 1 expected transudate as exudate out of 8 by Light’s criteria. Conclusion: Pleural fluid cholesterol is a simple, cost effective and useful parameter in differentiating pleural exudates from transudates, with the advantage of requiring only one laboratory determination and no simultaneous blood sample, as compared to the use of Light’s criteria.

Keywords: Pleural Fluid Cholesterol, Exudates and Transudates.