The test evaluates cell‑mediated immune response by measuring interferon‑gamma released from T‑cells exposed to TB‑specific antigens.

Unlike the traditional Mantoux tuberculin skin test, QFT is not affected by prior BCG vaccination.

Clinical uses include:

Detecting latent TB infection in high‑risk individuals.

Supporting diagnosis of active TB (in conjunction with clinical and microbiological findings).

Screening healthcare workers, immunocompromised patients, and contacts of TB cases.

Often performed alongside sputum AFB, GeneXpert MTB/RIF, and chest imaging for comprehensive TB evaluation.

Analyte: Interferon‑gamma release in response to TB antigens.

Normal Result: Negative (no significant interferon‑gamma release).

Abnormal Findings:

Positive result: Suggests TB infection (latent or active).

Indeterminate result: May occur in immunocompromised patients or due to technical issues.

Clinical Use:

Provides a highly specific marker of TB infection.

Helps guide diagnosis, screening, and treatment decisions.

Supports pulmonology, infectious disease, and public health evaluations.