Transudate | Exudate | |
---|---|---|
Appearance | clear | cloudy |
Fluid-Serum Protein Ratio | <0.5 | >0.5 |
Fluid-Serum LDH Ratio | <0.6 | >0.6 |
WBC Count | <1000/μL | >1000/μL |
RBC Count | <100,000/μL | >100,000/μL |
Spontaneous Clotting | No | Possible |
Pleural Fluid Cholesterol | <45-60 mg/dL | >45-60 mg/dL |
Pleural Fluid-Serum Cholesterol Ratio | <0.3 | >0.3 |
Pleural Fluid-Bilirubin Ratio | <0.6 | >0.6 |
Serum-Ascites Albumin Gradient | >1.1 | <1.1 |
Appearance | Clinical Significance |
---|---|
clear, pale yellow | normal |
turbid, white | bacterial infection, tuberculosis, immunologic disorder |
bloody | hemathorax (traumatic injury, appears streaked and uneven), hemorrhagic effusion, pulmonary embolis, tuberculosis, membrane damage |
milky, white | chylous material (thoracic duct leakage) |
milky, green tinge | pseudochylous material (chronic inflammation) |
brown | rupture of amoebic liver abscess |
black | Aspergillus |
viscous | malignant mesothelioma (increased hyaluronic acid) |
Chylous | Pseudochylous | |
---|---|---|
Cells Seen | predominantly lymphocytes | mixed cells |
Cholesterol Crystals | absent | present |
Triglycerides | >110 mg/dL | <55 mg/dL |
Sudan III stain | strongly positive | negative or weakly positive |
Cell | Appearance | Clinical Significance | Picture |
---|---|---|---|
neutrophils | increased in bacterial infection, pancreatitis and pulmonary infarction | ![]() | |
lymphocytes | prominent nucleoli, cleaved nuclei, may be seen with LE cells | increased in tuberculosis, viral infections, malignancy and autoimmune disorders | ![]() |
eosinophils | increased in pneumothorax and hemothorax, allergic reactions and parasitic infections | ![]() | |
mesothelial cells | pleomorphic; resemble lymphocytes, plasma cells and malignant cells; single round cell with abundant blue cytoplasm and round uniform dark purple nucleus (normal), or clustered multinucleated cells with varying amounts of cytoplasm, eccentric nuclei, and prominent nucleoli (“reactive”) | increased in pneumonia and malignancy, decreased in tuberculosis | ![]() ![]() |
plasma cells | seen in the absence of mesothelial cels | decreased in tuberculosis | ![]() |
malignant cells | nuclear and cytoplasmic irregularities, hyperchromatic nucleoli, cellular clumps with cytoplasmic molding (community borders), increased nuclear-to-cytoplasmic ratios | primary adenocarcinoma, small-cell carcinoma, metastatic carcinoma | ![]() |
Parameter | Important Values | Clinical SIgnificance |
---|---|---|
glucose | <60 mg/dL | tuberculosis, rheumatoid inflammation, and purulent infections |
lactate | elevated | bacterial infection |
pH | <7.0 | need for chest-tube drainage and antibiotics (pneumonia) |
<6.0 | esophageal rupture and influx of gastric fluid | |
0.30 degrees lower than the blood pH | acidosis | |
adenosine deaminase (ADA) | >40 U/L | tuberculosis and malignancy |
amylase | elevated | pancreatitis, esophageal rupture and malignancy |
Appearance | Clinical Significance |
---|---|
clear, pale yellow | normal or transudate |
turbid | infection, malignancy |
blood-streaked | malignancy |
grossly bloody | accidental cardiac puncture, misuse of anticoagulant medications |
milky | chylous or pseudochylous |
Appearance | Clinical Significance |
---|---|
clear, pale yellow | normal |
turbid | bacterial or fungal infection |
green or dark brown | presence of bile |
blood-streaked | trauma, tuberculosis, intestinal disorders or malignancy |
Differentiation between ascitic fluid transudates and exudates is more difficult than for pleural and pericardial effusions.
The serum-ascites albumin gradient (SAAG) is recommended over the fluid:serum total protein and LD ratios for the detection of transudates of hepatic origin.
Fluid and serum albumin levels are measured concurrently, and the fluid albumin level is then subtracted from the serum albumin level.
A difference (gradient) of 1.1 or greater suggests a transudate effusion of hepatic origin, and lower gradients are associated with exudative effusions.
Parameter | Important Values | Clinical Significance |
---|---|---|
glucose | decreased below serum levels | bacterial and tubercular peritonitis or malignancy |
amylase | increased | pancreatitis or gastrointestinal perforations |
alkaline phosphatase | increased | intestinal perforation |
blood urea nitrogen, creatinine | ruptured bladder or accidental puncture of the bladder during the paracentesis |