"Background: Pleural effusion is an excessive accumulation of fluid in the space lies between the lung and chest wall i.e. pleural space. In normal condition, pleural space contains 0.1–0.3 ml/kg body weight of fluid (near about of 10 ml of fluid on each side) between the parietal and visceral pleura.
Objectives: To investigate whether uric acid measurement in fluid is more sensitive and specific marker for differentiating between exu-dates and transudates, as confirmed clinically.
Materials and Methods: A total of 60 consecutive patients with di-verse etiologies having pleural effusion were selected for the study.
Results: Increase Uric acid level was observed in pleural fluid of transudative pleural effusion than exudative pleural effusion. It was also observed that the level of uric acid was more in pleural fluid than serum and ratio (pleural fluid / serum) of uric acid was â‰¥ 1 in tran-sudative conditions but in case of exudative condition the this ratio was < 1. The optimum cut-off level for P uric acid was 5.5 mg/dl with sensitivity of 94.00% and specificity of 83.00%. The optimum cut-off levels for P/S uric acid ratio was 1.0 with sensitivity of 96.00% and specificity of 92.16%.
Conclusion: Routine measurement of pleural fluid uric acid value and the calculation of fluid to serum total protein and lactate dehydro-genase (LDH) ratios will aid in differentiating exudates from tran-sudates.
Pleural effusion; exudates; transudates; uric acid