Quantiferon TB Gold
Improved testing for TB infection is now available
QuantiFERON-TB Gold is a modern alternative to the tuberculin skin test (TST or Mantoux). QuantiFERON-TB Gold is a blood test for TB infection. It measures the cellmediated immune response (cytokines) to very specific TB antigens. It is an interferon-gamma (IFN- ) release assay, commonly known as an IGRA4.
What is QuantiFERON-TB Gold?
QuantiFERON-TB Gold (QFT) is a simple blood test that aids in the detection of Mycobacterium tuberculosis, the bacteria which causes tuberculosis (TB). QFT is an interferon-gamma (IFN-γ) release assay, commonly known as an IGRA, and is a modern alternative to the tuberculin skin test (TST, PPD or Mantoux). Unlike the TST, QFT is a controlled laboratory test that requires only one patient visit and is unaffected by previous Bacille Calmette-Guerin (BCG) vaccination.
QFT is highly specific and sensitive: a positive result is strongly predictive of true infection with M. tuberculosis. However, like the TST and other IGRAs, QFT cannot distinguish between active tuberculosis disease and latent tuberculosis infection, and is intended for use with risk assessment, radiography, and other medical and diagnostic evaluations. Like any diagnostic aid, QFT cannot replace clinical judgment.
The US Centers for Disease Control (CDC) Guidelines recommend the use of IGRAs in all situations in which the TST was historically used, with IGRAs being the preferred test for persons who have been BCG vaccinated or are unlikely to return for TST reading.
The QFT advantage – three tubes, one clear result
QFT uses unique blood collection tubes that enable immediate exposure of viable blood lymphocytes to highly specific TB antigens (ESAT-6/CFP-10/TB-7.7(p4)) and test controls coated on the inner surface of the tubes. Antigen exposure produces a quantifiable immune response to aid in the diagnosis of TB infection.
- Nil tube - Negative control to adjust for background IFN-γ
- TB Antigen tube - To detect the CD4+ T cell responses to TB antigens
- Mitogen tube - Low response may indicate inability to generate IFN-γ
QFT is the most clinically tested and proven IGRA.
QuantiFERON-TB Gold is the most clinically tested and proven IGRA available (2). More than 30 million QFT tests have been sold across 130+ countries, including more than 7 million in 2015. Trust the only blood test for TB infection that offers:
- The most accurate and reproducible results for TB infection
- The confidence of more than 1200 clinical and scientific studies
- Convenient and objective ELISA technology
- Single visit testing
Changing the way the world looks at TB
- Unaffected by prior BCG vaccination
- High sensitivity in patients with rheumatic disease
- High specificity, virtually eliminating false-positive results seen
- with TST
- Proven performance in patients on immune suppression therapies
- (methotrexate, corticosteroids, TNF- inhibitors)
- Does not boost subsequent test results, ideal for serial testing
- Provides an objective, reproducible result unaffected by subjective
Reliable, meaningful results
The test is performed by collecting whole blood (1 mL) into each of three blood collection tubes. Tubes are incubated at 37oC for 16 to 24 hours. The IFNconcentration in the plasma is determined using a sensitive ELISA.