TB ELISPOT
| Category | Immunology |
|---|---|
| Test background |
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 %. |
| Clinical Indications |
TB infection |
| Reference range | Negative |
| 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 |