What is this test?
This laboratory test is performed on a pleural fluid sample to detect the presence and identify bacteria and fungi. This test helps the doctor in classifying bacteria grown in culture for starting the appropriate treatment.
Why is this test performed?
This test is performed:
- To identify the cause of bacterial or sometimes fungal infection
- To identify the shape and class of bacteria i.e. gram positive or gram-negative.
- What is gram-staining?
Gram-staining is a method of staining used in microbiology to detect the presence and identify the general type of bacteria or sometimes fungi in a sample taken from the site of a suspected infection; to generally classify bacteria grown in culture so that further identification tests can be performed and appropriate treatment given.
- What are the risks of this test?
- Partial or complete lung collapse
- Infection at the puncture site
- Bleeding
- Pulmonary edema
- Fluid re-accumulation
- Cough
- Respiratory distress.
- What is Thoracentesis?
Thoracentesis is a procedure to remove pleural fluid from the pleural space of the lung with the help of a needle. It is used for pleural fluid analysis and removal of excess pleural fluid.
- How to prepare for the test?
No special preparations are required for this test. Inform your doctor about your complete medical history especially of allergy, and bleeding problems.
- What is pleural effusion?
Pleural effusion is a disease characterized by accumulation of fluid in between the coverings (pleura) of the lung restricting the lung to inflate to its full capacity. It can be due to a variety of causes. Normally, only 10-20 ml of pleural fluid is present in the pleural space.
- What are the symptoms of pleural effusion?
- Shortness of breath
- Dry cough
- Chest pain
- Fever
- Chills
- Fatigue
- Inability to lie flat.
Positive or negative
Interpretation of test results:
- Negative: A negative test result means that either the infection is not caused by bacteria or the bacteria are very less in number to be seen on gram-stain
- Positive: A positive test result provides the following details about the bacteria:
- Gram-negative or positive
- Shape and size
- Presence of red or white blood cells
- Presence of bacteria inside cells.