An AFB-DNA (TB-PCR) Detection by Real-Time PCR with Reflex to Rifampicin Resistance by Ultra CBNAAT on Tissue is an advanced molecular test specifically designed to diagnose Histopathological or Extrapulmonary Tuberculosis (EPTB) within solid organ systems and structural tissues.

When tuberculosis manifests outside the lungs, it frequently forms deep-seated lesions or granulomas. Because the concentration of live bacteria in these dense tissues is often incredibly low (paucibacillary), traditional microscope smears and standard biopsy stains can easily miss them. This panel extracts the genetic blueprint (DNA) directly from tissue cells to deliver an incredibly rapid, ultra-sensitive diagnostic answer.

What Types of Tissue Specimens Are Evaluated?
This panel is performed on solid tissue biopsy specimens collected via needle aspiration, core biopsy, or surgical excision, including:

Lymph Nodes: Most commonly from cervical (neck), axillary, or mediastinal lymph nodes to diagnose TB Lymphadenitis.

Bone and Joint Tissue: Collected from suspected skeletal structures to identify bone TB or Pott’s Disease (spinal tuberculosis).

Gastrointestinal / Peritoneal Tissue: Biopsies taken from the bowel wall lining or omentum during an endoscopy or laparoscopy.

Pleural / Pericardial Tissue: Small structural samples taken from the protective sacs around the lungs or heart.

Skin / Soft Tissue: From non-healing chronic ulcers, nodules, or deep abscesses.

An AFB-Xpert Panel (M.Tb Detection & Rifampicin Resistance) by CBNAAT for extra-pulmonary samples is a rapid molecular test used to detect Mycobacterium tuberculosis (the bacteria that causes TB) and check if it is resistant to Rifampicin, a core first-line TB medication.

When performed on extra-pulmonary samples (tissue or fluid from outside the lungs), it is a crucial tool for diagnosing complex, hard-to-reach TB infections.

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

CBNAAT: Cartridge-Based Nucleic Acid Amplification Test. It is a fully automated PCR (polymerase chain reaction) test that looks for the DNA of the bacteria.

Extra-pulmonary samples: Samples taken from body parts other than the lungs.

2. Common Sample Types Used
Because extra-pulmonary TB can affect almost any organ, the test can be run on various non-sputum samples, including:

Fluids: Pleural fluid (lung lining), cerebrospinal fluid (CSF for TB meningitis), ascitic fluid (abdomen), or synovial fluid (joints).

Tissue: Lymph node aspirates (FNAC) or biopsy tissue from suspected organs.

Urine: Used in suspected urogenital TB.

3. What the Test Detects
The test provides two critical pieces of information simultaneously, usually within 2 hours:

M.Tb Detection (Positive/Negative): Confirms whether Mycobacterium tuberculosis DNA is present in the sample.

Rifampicin (Rif) Resistance (Detected/Not Detected): It targets the rpoB gene of the bacteria. If mutations are found in this gene, it indicates the strain is resistant to Rifampicin. Because Rifampicin resistance is highly correlated with multi-drug resistant TB (MDR-TB), this serves as a critical early warning.

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.