Pleural Fluid Analysis Test
A pleural fluid analysis is a group of tests that examine fluid that builds up between your lungs and chest wall. It helps find the cause of this fluid buildup, called pleural effusion.
What this test measures
A pleural fluid analysis measures the type and amount of fluid in the pleural space, including levels of protein and other substances, to determine if the fluid is transudate or exudate.
What your results mean
Reference ranges vary by laboratory and by your age and sex. MedlinePlus does not publish a single normal range for this test — always read your result against the range printed on your own lab report and discuss it with your provider.
Frequently asked questions
What is a pleural fluid analysis?
It is a group of tests that examine fluid that builds up in the space between your lungs and chest wall, called the pleural space.
Why is this test done?
It helps find the cause of a pleural effusion, which is too much fluid in the pleural space.
What do the results show?
Results show whether the fluid is transudate (watery, low protein) or exudate (cloudy, high protein), which narrows down possible causes.
What conditions cause transudate fluid?
Transudate is most often caused by heart failure, kidney disease, or liver disease including cirrhosis.
What conditions cause exudate fluid?
Exudate can be caused by infections like pneumonia, cancer, autoimmune diseases like rheumatoid arthritis, pancreatitis, or chest injuries.
Related lab tests
Sources
- MedlinePlus: Pleural Fluid Analysis — NIH MedlinePlus
Last updated . Information is aggregated from official public sources and is not a substitute for professional medical care.