T-SPOT.TB test results are available within one to two days. Other tests may take days or weeks.
Unlike the tuberculin skin test (TST or PPD), the T-SPOT.TB test does not require a follow up visit to the doctor’s office.
Sensitivity refers to how well a test detects the disease. With a sensitivity of ~95.0%, T-SPOT.TB is the most sensitive TB test currently available*.
Specificity is the ability of a test to identify uninfected people. Although there can be no gold standard for specificity, the specificity of the T-SPOT.TB test has been estimated to be 99.0%*.
Some TB tests may be less accurate in people with weakened immune systems or previous BCG vaccinations. The T-SPOT.TB test, however, is not affected by these factors. Therefore, even people in these groups will have highly reliable results when tested with the T-SPOT.TB test.*
Test accuracy will also depend on how a test can differentiate TB apart from other types of infections. Due to the use of the ESAT-6 and CFP 10 antigens the T-SPOT.TB test is excellent at distinguishing between TB and the most common non-tuberculosis bacteria.
* T-SPOT.TB Pivotal Clinical Trial Results. Sensitivity of 95.0% and 99.0% specificity after exclusion of borderline results. The study demonstrated no association between the T-SPOT.TB results and immunocompromised status or BCG vaccination. T-SPOT.TB US Pivotal Clinical Study, PI-TB-US-V1