Comparison of serum & pleural levels of NT-ProBNP in patients with acute dyspnea and pleural fluid referred to Emergency Department

Abstract

Pleural effusion is one of the most common manifestations of cardiac and non cardiac disease all over the world. The first step in the evaluation of patients with pleural effusion is to determine whether the effusion is a transudate or an exudate, that diagnostic Light criteria have been widely used. Although, this criteria are sensitive for identifying exudates, but they misclassify 15% to 25% of transudate as exudates. N-terminal B-type Natriuretic Peptide(NT-proBNP) is a cardiac neurohormone specifically secreted from the ventricles in response to volume expansion and pressure overload. This study aims at Comparison of serum and pleural levels of NT-ProBNP in patients with acute dyspnea and pleural fluid referred to Emergency Department and evaluating diagnostic value of serum and pleural NT-ProBNP in diagnosis of heart failure. In an analytic-descriptive cross-sectional study, 43 patients with acute dyspnea and pleural fluid in two groups (15 patients with CHF and 28 patients with other pathology) were analyzed in a 17 month period in Tabriz Emam Reza hospital. Samples of pleural fluid and serum were obtained from all patients on admission and NT-ProBNP was performed by electrochemiluminiscence immunoassay method. Also other biochemical analysis (albumin, total protein, cholesterol, triglyceride, amylase, LDH) were performed and gradient and ratio of this markers were accounted. The Mean +/- SD serum NT-proBNP levels in CHF and non CHF patients were 15423 +/- 3351 pg/ml and 4751 +/- 1616 pg/ml, respectively; and plural NT-ProBNP levels in CHF and non CHF patients were 14822 +/- 3249 pg/ml and 3569 +/- 1231 pg/ml, respectively. Using a cut-off value of 2350 pg/mL for serum and 1750 pg/ml for pleural samples, the accuracy of NT-proBNP for identifying pleural effusions from cardiac causes was 76%, the sensitivity and specificity was 93.3% and 76.9%, respectively; The positive and negative likelihood ratio was 3 and 0.10, respectively. The positive and negative predictive value was 60% and 95%, respectively. In this study Light criteria had 40% sensitivity and 78% specificity in identifying cardiac causes of pleural effusion. NT-proBNP is better than Light's criteria and a useful marker for the diagnosis of pleural effusions from heart failure when measured in either serum or pleural fluid. [Ali Taghizadieh, Alireza Aala, Amir Hossein Jafari Roohi, Mohammad Reza Gaffary, Peyman Moharramzadeh, Mahboub Pouraghaei, Amir Gaffarzad, Omid Mashrabi. Comparison of serum & pleural levels of NT-ProBNP in patients with acute dyspnea and pleural fluid referred to Emergency Department. Life Sci J 2012;9(4):1432-1438] (ISSN:1097-8135). http://www.lifesciencesite.com. 219