Performance T-SPOT.TB

T-SPOT.TB Performance

The T-SPOT.TB test difference

For many years, there was only one way to test for tuberculosis (TB): the tuberculin skin test (TST). This is no longer the case, as there are now two categories of tests to detect TB infection:

Performance T-SPOT.TB

The tuberculin skin test1

The TST has been used to detect TB infection for over 100 years. They require an intradermal injection of a small amount of purified protein derivative (PPD), a TB antigen, into the skin. In 48-72 hours, the resultant induration is measured.

Performance T-SPOT.TB

Interferon-gamma release assays

Interferon-gamma release assays (IGRAs), which include the T-SPOT.TB test, are blood-based tests. The technology is based on the release of interferon-gamma secreted by individual effector T cells (both CD4+ and CD8+) after being stimulated by TB-specific antigens.                    

Accurate across patient populations
TB test considerations IGRAs TST
T-SPOT.TB2 QFT®-Plus3 LIAISON® QFT-Plus4
Utility in
immunocompromised
patients		 Checkmark

XWarning in package insert that the predictive value of a negative QFT®–Plus result in immunosuppressed persons has not been determined

XLimitation in package
insert stating that
performance of the
test has not been
extensively evaluated
in several groups
of individuals,
including some
populations who are
immunocompromised

Studies have
demonstrated
limitations in
immunocompromised patients1

Sensitivity and specificity > 95%

 Checkmark X X X
FDA-approved borderline zone Checkmark X X X

No cross-reactivity with BCG vaccine

 Checkmark Checkmark Checkmark X

Objective test results

 Checkmark Checkmark Checkmark X

Consistent results
TB test considerations T-SPOT.TB QFT®-Plus LIAISON® QFT-Plus4 TST
< 1% uninterpretable test results Checkmark0.6% invalid rate5 X2.5% indeterminate rate3 X3.1% indeterminate rate N/A
Conversion rate < 1% in serial testing Checkmark0.8%6 XQFT®-Plus 4.3%7
QFT®-Gold 4.4%8		 N/A* N/A

One tube with no refrigeration
TB test considerations T-SPOT.TB2 QFT®-Plus3 LIAISON® QFT-Plus4 TST
On-site incubation or refrigeration of specimen is never required Checkmark X X N/A
Single, streamlined blood collection and process Checkmark

X3 possible collection methods requiring use of 1 or 4 tubes with up to 9 steps required

X3 possible collection methods requiring use of 1 or 4 tubes with up to 9 steps required

 N/A
A single visit is required

Checkmark

 Checkmark Checkmark X

Unique CPT® code9

 
CPT® code 86481* 86480* 86480*
Applicable test The T-SPOT.TB test  QuantiFERON®-TB Gold Plus (QFT®-Plus) LIAISON® QFT-Plus
Description Tuberculosis test, cell mediated immunity antigen response measurement; enumeration of gamma interferon-producing T-cells in cell suspension Tuberculosis test, cell mediated immunity measurement of gamma interferon producing antigen response Tuberculosis test, cell mediated immunity measurement of gamma interferon producing antigen response

Learn more about the
T-SPOT.TB test

Contact Us