Performance T-SPOT.TB


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
Utility in
Checkmark X


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


Studies have demonstrated limitations in immunocompromised patients1

Sensitivity and specificity > 95%

Checkmark X X
FDA-approved borderline zone Checkmark X X

No cross-reactivity with BCG vaccine

Checkmark Checkmark X

Objective test results

Checkmark Checkmark X

Consistent results

TB test considerations T-SPOT.TB QFT®-Plus TST
< 1% uninterpretable test results Checkmark0.6% invalid rate4 X2.5% indeterminate rate3 N/A
Converison rate < 1% in serial testing Checkmark0.8%5 XQFT®-Plus 4.3%6
QFT®-Gold 4.4%7

One tube with no refrigeration

TB test considerations T-SPOT.TB2 QFT®-Plus3 TST
On-site incubation or refrigeration of specimen is never required Checkmark 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

A single visit is required


Checkmark X

Unique CPT® code8

CPT® code 86481* 86480*
Applicable test The T-SPOT.TB test  QuantiFERON®-TB Gold Plus (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

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T-SPOT.TB test

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