Pleural effusion - laboratories in common cause 1. Normal: - Clear ultrafiltrate of plasma that originates from the parietal pleura - pH 7.60-7.64 - Protein content less than 2% (1-2 g/dL) - Fewer than 1000 WBCs per cubic millimeter - Glucose content similar to that of plasma - Lactate dehydrogenase (LDH) less than 50% of plasma 2. Most common cause - Left heart failure - Pneumonia - Malignancy - Pulmonary embolism - Viral disease Add: Tuberculosis, empyema 3. Case a. Left heart failure - Clear/serous/light yellow - Nucleated cells <5k - Protein less than 2% - Serum LDH ratio <0,6 or Pleural fluid LDH<0,67 of upper limit of normal for serum LDH - Glucose content similar to that of plasma. b. Pneumonia/Empyema - Purulent/turbid/brown - Nucleated cells>50k, neutrophilia - Glucose <60mg/dL - LDH>1000 IU/L in empyema - pH<7,3. c. Malignancy - Bloody/serosanguineous - Nucleated cells<5k, eosinophil>10% - LDH >1000 UI/L - Glucose <60 mg/dL - pH <7,3 d. Tuberculosis - Nucleated cells <5k, lymphocytosis (85%) - Protein > 4%. - Glucose <60 mg/dL Soucre: Medscape, Washington's manual of medical therapeutics. . Pleural effusion - laboratories in common cause 1. Normal: - Clear ultrafiltrate of plasma that originates from the parietal pleura - pH 7.6 0-7 .64 - Protein content less. neutrophilia - Glucose <60mg/dL - LDH>1000 IU/L in empyema - pH<7,3. c. Malignancy - Bloody/serosanguineous - Nucleated cells<5k, eosinophil>10% - LDH >1000 UI/L - Glucose. - Pneumonia - Malignancy - Pulmonary embolism - Viral disease Add: Tuberculosis, empyema 3. Case a. Left heart failure - Clear/serous/light yellow - Nucleated cells <5k - Protein