ABSTRACT
Pleural effusion is the accumulation of excessive fluid in the pleural space. One way for detection of its etiology is to examine the fluid for its exudative or transudative origin. Until now, the best criterion is Light Criteria; following by is serum and pleural albumin gradient. This study was done to examinate the possibility of using albumin gradient as first criteria instead of Light Criteria. In this descriptive study 100 patients with pleural efftision, detected by plane chest X-ray were studed. Light Criteria and albumin gradient for each patient was obtained. Regarding to final diagnosis, results from albumin gradient and Light Criteria were compared. Individual and laboratory data were gathered in a questionnaire and analyzed using SPPS software and descriptive statistics. Based on the clinical diagnosis. 70 patients had an exudative pleural effusion and 14 transudative pleural effusions. Nine patients had no final diagnosis, one patient died before preparation of final diagnosis and six patients had pulmonary emboli that can produce both exudative and transudative pleural effusion. In patients with final diagnosis, 77 had exudative and 13 had transudative fluid. By albumin gradient 41 had exudative and 49 transudative fluid. Light criteria could diagnose 69 of all 70 exudative fluid and 11 of 14 transudative fluid, properly. In albumin gradient method it was 41 and 14, respectively. In according to our study albumin gradient is not suitable as first criteria to differentiate exudative and transudative pleural effusion. In cases that the pleural fluid has a transudative feature in clinic, but an exudative characteristic according to Light Criteria, albumin gradient is a useful criterion for exact diagnosis