Diagnosis of pleural effusion is often difficult as it is developed due to various etiologies. Identifying the causes of pleural effusions by pleural fluid analysis is essential for proper treatments. The present article describes the causes and diagnosis of pleural effusion. General Approach: The first step in the evaluation of patients with pleural effusion is to determine whether the effusion is a transudate or an exudate.
If the patient has a transudate effusion, therapy should be directed toward the underlying heart failure or cirrhosis. If the patient has an exudative effusion, attempts should be made to define the etiology. CLINICAL RECOMMENDATIONS: Thoracentesis should be performed in all patients with more than a minimal pleural effusion unless clinically evident heart failure is present. An effusion is exudative if it meets any of the following three criteria: (1) The ratio of…
