Description
The QuantiFERON®-TB Gold Plus blood test is a highly accurate, FDA-approved method for detecting Mycobacterium tuberculosis infection, the bacteria that causes tuberculosis (TB). Unlike the traditional TB skin test, this blood test requires only one visit, provides objective results, and is not affected by prior BCG vaccination.
This test is used to detect latent TB infection (LTBI) or active TB disease and is commonly required for employment, school, immigration, or healthcare clearance.
Purpose of the Test
- Detect latent TB infection (no symptoms, but infection is present)
- Aid in diagnosis of active TB (symptomatic, contagious form)
- Screen individuals who may have been exposed to TB
- Meet school, workplace, or immigration health requirements
- Provide an alternative to the tuberculin skin test (TST/PPD)
Who Should Consider This Test?
- Healthcare workers or hospital staff
- School teachers, daycare workers, and students
- Individuals applying for immigration or permanent residency
- People with known exposure to TB
- Patients who have received the BCG vaccine (skin tests may show false positives)
- Individuals with weakened immune systems or chronic conditions (e.g., diabetes, HIV)
What the Test Measures
The QFT-Plus test measures your immune system’s interferon-gamma (IFN-γ) response to specific TB antigens. A positive result suggests TB infection and may require follow-up evaluation with a chest X-ray or additional testing.
Unlike the skin test, results are not affected by previous BCG vaccination or most non-TB mycobacteria.
Fasting Required?
No fasting required.
