QuantiFERON-TB Gold (IGRA) measures interferon-gamma released by your immune cells when exposed to TB proteins.
Detects TB infection, including latent (silent) TB — useful before starting biologic/immunosuppressive medicines, in close contacts and healthcare workers. It is not affected by BCG vaccination.
Cough for more than 2 weeks, breathlessness, wheezing, fever with chest symptoms, or TB exposure.
No fasting needed.
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No. It shows TB infection; your doctor will use symptoms, X-ray and other tests to decide if TB is active.
No fasting is needed. You can eat and drink normally unless your doctor has advised otherwise.
Usually a blood sample; for some infections a swab, CSF, urine or other sample is used — as advised by your doctor.
Usually within 2–3 days after the sample reaches the lab. You will receive the report online.