To determine the diagnostic value of serum-effusion albumin gradient by using Roth ’s criterion.To compare it with Light’s traditional criteria according to which pleural fluid is exudate if it met any of the following criteria:a. pleural fluid/ serum total protein > 0.5b. pleural fluid LDH > 200 IU / Lc. pleural fluid / serum LDH > 0.6
The present study was conducted on 50 consecutive patients suffering from pleural effusion. Total Protein concentration, LDH level and albumin concentration were measured in serum and pleural fluid of all patients. All the cases were subjected to detailed history taking, general physical examination, chest radiograph and various laboratory tests to arrive at a clinical diagnosis.
Out of 50 patients 36 (72%) were of exudative pleural effusion and 14 (28%) were of transudative pleural effusion. Tuberculosis (22 cases, 61.11%) was the most common cause of exudative pleural effusion in our study followed by paraneumonic (9 cases) and neoplasm (5 cases) . The causes of transudative pleural effusion were, congestive cardiac failure (9 cases), nephrotic syndrome (3 cases) and renal failure (2 cases). By applying Light’s criteria, 1 case of exudative pleural effusion and 3 cases of transudative pleural effusion were misclassified yielding a sensitivity and specificity of 97.22 % and 78.57% respectively. All the misclassified cases of transudative pleural effusion were on diuretic therapy. Using serum- effusion albumin gradient, one case of exudative pleural effusion was misclassified while all cases of transudative pleural effusion were correctly classified yielding a sensitivity and specificity of 97.22% and 100% respectively.CONCLUSIONS: It is concluded from the present study that the major disadvantage of light’s criteria appears to be the misclassification trasudates as exudates, especially in cases of congestive cardiac failure on diuretic therapy.CLINICAL IMPLICATION: Misclassification of transudates as exudates may lead to unnecessary and costly investigations in patients.Serum- effusion albumin gradient is a reliable and cost effective criterion too differentiating exudates and transudates especially in cases of congestive cardiac failure treated with diuretics.
G. Singh, none.