LOINC display name : M. tuberculosis stim IFN-g CFP10 Ag spot count (Bld) [#];
LOINC long common name : Mycobacterium tuberculosis stimulated gamma interferon CFP10 Ag spot count [#] in
Blood;
LOINC short name : M TB IFN-g.CFP10 Ag Bld;
LOINC description : The count of spots (0 to 20) in a patient's T cells that represent IFN-γ released
in response to the presence of M. tuberculosis culture filtrate protein 10 (CFP10)
antigens. The spot count provides a measurement of the abundance of Mycobacterium
tuberculosis sensitive effector T cells in the peripheral blood. This term is based
on, but not limited in use to, Oxford Immunotec's T-SPOT.TB assay, used to diagnose
M. tuberculosis. T-SPOT.TB assay uses enzyme-linked immunospot (ELISPOT) methodology
to enumerate M. tuberculosis-sensitized T cells by capturing interferon-gamma (IFN-y)
in the vicinity of T cells in the patient's whole blood. In the T-SPOT.TB assay, the
test result is positive if [ESAT-6 (Panel A) - negative control spots] and/or [CFP10
(Panel B) - negative control spots] is greater than or equal to 8 spots. The test
result is negative if both [Panel A - negative control] and/or [Panel B - negative
control] is less than or equal to 4 spots.;