In the discrimination of transsuda-exuda of plevral fluidsvalue of plevral liquid and serum nt-probnp level

The most common reasons are congestive heart failure, end stage renal failure and cirrhosis for transudative; pneumonia, pulmonary embolism and malignancy for the exudative effusions. Recently, we used Light criterion for the standard approach to pleural effusions. However, in some situations like heart failure, Light criterions may cause expounding exudative effusion of transudative effusions. In these circumstances, it is suggested that albumin gradient and pleural fluid and serum NT-proBNP which are recently in use may keep from requesting useless examinations. This study is designed to investigate the role of the pleural fluid and serum NT-proBNP measurements in the differential diagnosis of pleural effusions secondary to heart failure. 91 patients with pleural effusion were included in this study. Patients were divided into three groups; 23 patients secondary to heart failure (Group 1), 25 patients due to noncardiac transudative effusion (Group 2) and 43 patients due to exudative reasons (Group 3). Pleural fluid and serum NT-proBNP levels of Group 1 patients were statistically high and significant (p< 0,001). There was a significant correlation between serum and blood NT-proBNP levels. According to ROC slope analysis, when pleural NT-proBNP levels as 2184 pg/ml and 2325 pg/ml for heart failure, sensitivity was assigned as high, specifity and accuracy were low. In Group 2 patients with chronic renal failure, levels of NT-proBNP were statistically significantly different and higher than Group 1 patients and other reasons (p< 0,001). In conclusion, we determined that pleural fluid and serum NT-proBNP have high specifity in diagnosis of pleural effusions due to heart failure. Moreover, a significant correlation was found between serum and fluid NT-proBNP levels. Therefore, we thought that serum NT-proBNP measure may be determinative and may be preferred to thorasynthesis because of being less invasive in patients who are compatible to heart failure clinically. Otherwise, we believe that the measure of albumin gradient which is less cost effective could be prefered in patients with heart failure which have exudative effusion according to Light criterion. Key words; Pleural flouid, Light criterion, transudative, exudative, NT-proBNP, heart failure, albumin gradient.