Pleural fluid smear is a laboratory procedure to check for bacteria, fungi, or abnormal cells in the fluid that may be found in the space around the lungs (called a pleural effusion).
A health care provider examines a sample of pleural fluid under the microscope. If the smear detects bacteria or fungi, other methods may be used to identify those organisms.
The sample is obtained through a procedure called thoracentesis. For information about this test and its risks, see thoracentesis.
The test is performed if you have a pleural effusion and its cause is not known, especially if the health care provider suspects an infection or cancer.
Normally, no bacteria or fungi are present in the pleural fluid.
Normal value ranges may vary slightly among different laboratories. Talk to your doctor about the meaning of your specific test results.
Positive results may indicate that bacteria or cancer cells are present. Other tests can help identify the specific type of infection or cancer.