Mycobacterium tuberculosis detection and Rifampin resistance (rpoB gene), Rapid by real-time PCR : 1005092

Notes: 1. This test MUST have an AFB culture associated with it. This test may be ordered at the same time that the sample is submitted for AFB culture. 2. Rifampin-resistance should be confirmed by alternate methods since mechanisms of rifampin resistance other than those detected by this test may exist that may be associated with a lack of clinical response to treatment.

Test Code
RTBRIF or 1005092

Alias/See Also
Acid-Fast Bacilli; AFB; Acid-Fast Bacilli; MTB; TB (Tuberculosis); Tubercle Bacilli; Mycobacterium

CPT Codes

The following specimen types are acceptable: Respiratory: Sputum, Bronchial lavage, Bronchial brushes, Bronchial washings Non-Respiratory: CSF; Other Sterile Body Fuilds (Ascites, Paracentesis, Pelvic, Peritoneal, Pleural, Synovial, Thoracentesis fluids, etc.); Tissue (Fresh or Frozen) Collection Instructions for Respiratory Specimens: Sputum (Preferred Specimen Type): 1. Sputum should be collected under the supervision to ensure proper collection. A first morning specimen is preferred. 2. Instruct the patient to cough deeply to bring up sputum from the lungs (Instruct patient to NOT collect nasal discharge or saliva). 3. Expectorate the sputum into a sterile, leak-proof container. Continue the procedure until approximately 5 mL of sputum are collected. Securely fasten the top of the container and place in a plastic bag. Bronchial lavages, brushes and washings (Also acceptable): 1. Collect as much bronchial material as possible, avoiding collection of material in areas that may be contaminated with the local anesthetic. 2. Place the washings or brushes into a sterile, leak-proof tube. Brushes should be placed into a small volume of saline to keep from drying.

Transport Container
Submit Respiratory specimens in a sterile, leak-proof container.

Submit 1 mL CSF in a sterile plastic screw capped container (Min. 0.5 mL).

Submit 2 mL Other Sterile Body Fluids in a sterile plastic screw capped container (Min. 1 mL).

Submit Fresh and Frozen Tissue in a sterile container. Frozen tissue must be in OCT compound.

Note: Do not centrifuge any specimen type.

Transport Temperature
Respiratory, CSF, Other Sterile Body Fluid, or Fresh Tissue: Refrigerated
Frozen Tissue: Frozen

Specimen Stability
Ambient: 3 days; Refrigerated: 7 days; Frozen: 1 month

Qualitative real-time Polymerase Chain Reaction (PCR)

Setup Schedule
Sunday - Saturday

Report Available
1 day

Reference Range
Target Not Detected

Clinical Significance
Globally, Mycobacterium tuberculosis (MTB) accounts for 2 billion infections, 9 million patients with active disease and 1.4 million deaths every year. MTB is spread from person-to-person via respiratory transmission. Active pulmonary TB is a highly infectious airborne disease. All patients in healthcare facilities with suspected TB should be maintained in respiratory isolation according to recommended infection control guidelines. Standard treatment regimens for tuberculosis involve prolonged administration of multiple drugs and is usually highly effective. However, it has the potential to become resistant to many or all of the antibiotics currently used if appropriate management is not initiated promptly. Rifampin resistance is often an indication of multidrug resistance to tuberculosis (MDR TB), which is defined as resistance to at least rifampin (RIF) and isoniazid (INH). In the United States, overall MDR TB rate is approximately 1.8%. MTB-complex strains that are resistant to one or more of first line drugs require individualized treatment. Therefore, rapid diagnosis of MTB and typing of key resistance markers in patient specimens is of clinical and public health importance.

Conventional culture methods can generally detect MTB in 2 to 3 weeks, although up to 8 weeks of incubation may be required in some instances. This rapid PCR assay detects MTB complex DNA and rifampin-resistance associated mutations of the rpoB gene directly from respiratory specimens without waiting for growth in culture. Rifampin-resistance should be confirmed by alternate methods since mechanisms of rifampin resistance other than those detected by this test may exist that may be associated with a lack of clinical response to treatment. The rapid PCR results must be used in conjunction with mycobacterial culture to address the risk of false negative results and to recover the organisms for further characterization and drug susceptibility testing.

Performing Laboratory
med fusion

The CPT Codes provided in this document are based on AMA guidelines and are for informational purposes only. CPT coding is the sole responsibility of the billing party. Please direct any questions regarding coding to the payor being billed. Any Profile/panel component may be ordered separately. Reflex tests are performed at an additional charge.