An AFB-Xpert Panel (M.Tb Detection & Rifampicin Resistance) by CBNAAT for pulmonary samples is a highly efficient, automated molecular test. It serves as the frontline tool for rapidly diagnosing Tuberculosis (TB) in the lungs and checking if the bacteria are resistant to one of the most powerful first-line TB medications, Rifampicin.

Unlike extra-pulmonary testing, which deals with fluids and tissues from other organs, pulmonary testing specifically evaluates secretions from the respiratory tract.

1. What does the name mean?
AFB: Acid-Fast Bacilli (the class of bacteria to which Mycobacterium tuberculosis belongs).

CBNAAT: Cartridge-Based Nucleic Acid Amplification Test (commonly known as the GeneXpert test). It uses PCR technology to multiply and detect the DNA of the TB bacteria.

Pulmonary samples: Samples originating from the lungs and respiratory airways.

2. Common Pulmonary Sample Types
Because pulmonary TB directly affects the lungs, the sample types are respiratory secretions:

Sputum (Spontaneous): The thick mucus coughed up deeply from the lungs. This is the most common sample type.

Induced Sputum: If a patient cannot cough up sputum naturally, they inhale a sterile saline mist to help loosen secretions.

Bronchoalveolar Lavage (BAL): Fluid collected during a bronchoscopy, where a doctor passes a small scope into the lungs and flushes the area with saline. This is often used for complex or hard-to-diagnose cases.

Gastric Aspirate/Lavage: Commonly used in young children who cannot expectorate (spit out) sputum and instead swallow their respiratory secretions overnight.