Clinical Manifestations And Diagnostic Approache Of Pleural EffusionClinical ManifestationsAsymptomaticPleurtic chest painCoughDyspneadullness to percussiondecreased breath soundsegophony at the upper level of the effusion decreased tactile fremitusAPPROACH TO PATIENTS WITH PLEURAL EFFUSIONA diagnostic thoracentesis should be performed on nearly every patient with free pleural fluid that measures more than 10mm on the decubitus radiograph

Thoracentesis is a safe procedure when performed by an experienced operatorit can be safely performed in :patients with coagulopathies thrombocytopenia in patients on positive mechanical ventilationultrasound guidance for thoracentesis on small or multiloculated effusions in patients with poor lung function Bulous lung diseaseThe first question that should be answered with the diagnostic thoracentesis is whether the patient has a transudative or an exudative pleural effusion Exudative pleural effusions meet at least one of the following criteria, whereas transudative pleural effusions meet none (1) pleural fluid proteintoserum protein greater than 0.50(2) pleural fluid LDHtoserum LDH greater than 0.60 (3) pleural fluid LDH greater than two thirds of the upper normal limit for serum. transudative pleural effusionIf none of these criteria is met,The previously discussed criteria may misidentify a transudative effusion as an exudative effusion in as many as 25% of cases. If a patient appears to have a transudative effusion clinically, additional tests can be assessed to verify its transudative etiology. If the difference between the protein concentration of serum and the pleura exceeds 3.1gm/dL, the patient in all probability has a transudative effusion.TRANSUDATIVE PLEURAL EFFUSIONS Congestive heart failure Pericardial disease Hepatic hydrothorax Nephrotic syndrome Peritoneal dialysis Urinothorax Myxedema Fontan procedure Central venous occlusion Subarachnoid-pleural fistula Veno-occlusive disease Bone marrow transplantation Iatrogenic

CHF and cirrhosis are responsible for almost all transudative pleural effusions. EXUDATIVE PLEURAL EFFUSIONSNeoplastic diseases : Metastatic disease Mesothelioma Primary effusion lymphoma Pyothorax-associated lymphoma

Infectious diseases : Pyogenic bacterial infections Tuberculosis Actinomycosis and nocardiosis Fungal infections Viral infections Parasitic infections

Pulmonary embolism Gastrointestinal disease : Esophageal perforation Pancreatic disease Intra-abdominal abscesses Diaphragmatic hernia Postabdominal surgery

Collagen vascular diseasesRheumatoid pleuritis Systemic lupus erythematosu Drug-induced lupus Immunoblastic lymphadenopathy Sjgren's syndrome Churg-Strauss syndrome Wegener's granulomatosis

Postcardiac injury syndrome Postcoronary artery bypass surgery Asbestos exposure Sarcoidosis Uremia Meigs syndrome Ovarian hyperstimulation syndrome Yellow nail syndrome

Drug-induced pleural diseaseNitrofurantoin DantroleneMethysergide Bromocriptine Procarbazine Amiodarone Dasatinib

Radiation therapy Electric burns Iatrogenic injury Hemothorax Chylothorax

Pneumonia, malignant pleural disease, pulmonary embolism, and gastrointestinal disease account for at least 90% of all exudative pleural effusions

Appearance of Pleural FluidThe gross appearance of the pleural fluid should always be described and its odor noted

If the pleural fluid smells putrid, the patient has a bacterial infection (probably anaerobic) of the pleural space. If the fluid smells like urine, the patient probably has a urinothorax.If the pleural fluid is bloody, a pleural fluid hematocrit should be obtained. If the pleural fluid hematocrit is greater than 50% that of the peripheral blood, the patient has a hemothorax and the physician should strongly consider inserting chest tubes. If the pleural fluid hematocrit is less than 1%, the blood in the pleural fluid has no clinical significance. If the pleural fluid hematocrit is between 1% and 50%, the patient most likely has malignant pleural disease, a pulmonary embolus, or a traumatically induced pleural effusion.The supernatant of the pleural fluid should be examined if the pleural fluid is turbid, milky, or bloody. If the pleural fluid is turbid when originally obtained, but the turbidity clears with centrifugation, the turbidity is due to cells or debris in the pleural fluid. If the turbidity persists after centrifugation, the patient probably has a chylothorax or a pseudochylothorax. Pleural Fluid ProteinThe pleural fluid protein level tends to be elevated to a comparable degree with all exudative pleural effusions and is, therefore, not generally useful in the differential diagnosis of an exudative pleural effusion.if the protein level is above 5.0g/dL, the likelihood of the diagnosis of tuberculous pleurisy is increased. If the pleural fluid protein level is very low (