AFB C/S (Pleural Fluid for Mycobacterium Tuberculosis)

Specimen Required

FLUID (All Body Fluid)

Fasting Required

Purpose of the Test

The AFB C/S (Pleural Fluid for Mycobacterium tuberculosis) test is ordered to detect and identify the presence of Mycobacterium tuberculosis, which is the bacteria that causes tuberculosis (TB), in the pleural fluid. This test helps in the diagnosis of pleural TB, which is a form of extrapulmonary TB that affects the pleura, the thin membrane that surrounds the lungs and lines the chest cavity.

When this test is required

The AFB C/S (Pleural Fluid for Mycobacterium tuberculosis) test is requested when a person has symptoms of pleural TB, such as chest pain, shortness of breath, cough, and fever, and the healthcare provider suspects TB as the underlying cause. The test may also be ordered if a person has a history of TB exposure or if they are immunocompromised.

What the Test Detects

The AFB C/S (Pleural Fluid for Mycobacterium tuberculosis) test involves two parts: 1) Acid-fast bacilli (AFB) stain: This test involves staining the pleural fluid with a special dye that can identify acid-fast bacteria, including Mycobacterium tuberculosis. The stained fluid is then examined under a microscope to look for the presence of AFB. 2) Bacterial culture and sensitivity (C/S): This test involves placing a small amount of pleural fluid onto a culture medium that supports the growth of Mycobacterium tuberculosis. The medium is then incubated for several weeks to allow the bacteria to grow. Once the bacteria have grown, they can be identified using various biochemical tests and their sensitivity to different antibiotics can be determined.

Preparation for the Test

No special preparation is required for the AFB C/S (Pleural Fluid for Mycobacterium tuberculosis) test.

Sample Requirements

The test requires a sample of pleural fluid, which is obtained by a healthcare provider using a needle inserted into the pleural space between the lungs and the chest wall. The fluid is then collected in a sterile container and sent to the laboratory for testing.

Additional Notes

The AFB C/S (Pleural Fluid for Mycobacterium tuberculosis) test is just one of several tests that may be ordered to diagnose pleural TB. Other tests, such as chest X-rays, CT scans, and biopsy, may also be necessary depending on the suspected underlying cause.

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