QUANTIFERON (TUBERCULOSIS INTERFERON GAMMA RELEASE ASSAY,TB-IGRA)

QuantiFERON-TB Gold (TB-IGRA) is a laboratory blood test that measures interferon-gamma (IFN-γ) released by T‑cells in response to Mycobacterium tuberculosis–specific antigens. The assay uses specially prepared tubes (nil, TB antigen(s), and mitogen), incubates the blood with these antigens, and quantifies IFN-γ by ELISA to provide a quantitative result reported in IU/mL. This test is important because it offers high specificity for latent tuberculosis infection, is not affected by prior BCG vaccination, and is widely used for screening in clinical and public‑health settings.

The QuantiFERON test is recommended for screening close contacts of active TB cases, for pre-treatment evaluation before immunosuppressive or biologic therapy, and for workplace or pre-visa health checks where latent TB detection is required. While valuable for detecting latent infection, it does not distinguish latent from active TB disease and can yield indeterminate results in immunocompromised individuals; positive or indeterminate findings should be followed up by a clinician for further assessment and management. In Dubai, Touch Connect provides at‑home collection by certified technicians with rapid transport to accredited labs, ensuring timely, lab‑grade reporting suitable for clinical decision‑making.

• Nil (negative control) — IFN-γ
• TB Antigen Tube 1 (TB1) — IFN-γ
• TB Antigen Tube 2 (TB2) — IFN-γ
• Mitogen (positive control) — IFN-γ
• IFN-γ concentration (IU/mL) and qualitative interpretation (Positive/Negative/Indeterminate)

• Screening close contacts of confirmed active TB cases
• Pre-employment, pre-visa, or occupational health screening (including healthcare workers)
• Before starting immunosuppressive therapy or biologic agents (e.g., anti-TNF)
• Prior to organ transplant, chemotherapy, or other high-risk clinical interventions
• As follow-up or confirmation after a positive tuberculin skin test, especially in BCG-vaccinated individuals

• High specificity with minimal interference from prior BCG vaccination
• Single blood draw with quantitative, lab‑grade IFN-γ results
• At‑home collection by certified phlebotomists with prompt laboratory processing
• Fast reporting suitable for clinical decisions and pre-treatment clearance
• Useful for public health screening, occupational clearance, and pre-immunosuppression assessment

• Venous blood draw into QuantiFERON tubes performed at home by a certified technician
• No fasting required; continue regular medications unless advised otherwise by your clinician
• Inform the technician about immunosuppressive drugs, recent live vaccinations, or prior TB treatment
• Time‑sensitive handling: samples must be incubated and delivered to the laboratory promptly for accurate results