This assay detects interferon-gamma (IFN-γ) secretion in response to stimulation with Mycobacterium tuberculosis antigens. A positive test indicates presence of TB infection but cannot be used to distinguish active disease from latent infection. The negative predictive value of this test for TB infection is 98 %.
|Sample & container required||8mL sodium citrate (pale blue top) or 10 mL heparin (green top);
Samples must be received in the laboratory (Charing Cross) by 2pm Monday to Friday for the test to be performed.
|Sample volume||See above|
|Turnaround time||4 days|