Role of pleural fluid cholesterol in differentiating transudative from exudative pleural effusion
Guleria, R.; Agarwal, S.R.; Sinha, S.; Pande, J.N.; Misra, A.
National Medical Journal of India 16(2): 64-69
2003
ISSN/ISBN: 0970-258X PMID: 12816183 Document Number: 558049
Background: Pleural fluid cholesterol has been reported to be useful in distinguishing between transudative and exudative pleural effusion. However, the difference in lipid profile between tubercular and non-tubercular pleural effusion has not been studied. Methods: The lipid profile of pleural fluid in 50 patients with exudative (25 tubercular and 25 non-tubercular) and 25 with transudative effusion was studied. The diagnosis was based on clinical criteria and/or a positive diagnosis from another site. Results: The criteria that best identified an exudative pleural effusion were pleural fluid cholesterol gtoreq60 mg/dl, pleural fluid to serum cholesterol ratio gtoreq0.4, pleural fluid triglyceride gtoreq40 mg/dl and pleural fluid to serum triglyceride ratio gtoreq0.3. Pleural fluid cholesterol had a sensitivity of 88% and a specificity of 100% for exudates with an accuracy of 92%. Pleural fluid to serum cholesterol ratio had a sensitivity of 98% and a specificity of 84%. These results were superior to the criteria proposed by Light et al. (sensitivity 98% and specificity 80%). Conclusion: Pleural fluid cholesterol estimation is an effective and cost-efficient method of differentiating exudative from transudative pleural effusion. The lipid profile does not help in diagnosing tubercular effusion.