74277-5
LaboratoryMycobacterium tuberculosis stimulated gamma interferon CFP10 Ag spot count [#] in Blood
Definition
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.
LOINC 6-Axis Classification
Component
Mycobacterium tuberculosis stimulated gamma interferon.CFP10 Ag spot count
Property
Num
Time Aspect
Pt
System
Bld
Scale Type
Qn
Method Type
N/A
Details
Class
MICRO
Order/Observation
Both
Short Name
M TB IFN-g.CFP10 Ag Bld
Display Name
M. tuberculosis stim IFN-g CFP10 Ag spot count (Bld) [#]
Related Names
Frequently Asked Questions
What is LOINC code 74277-5?
LOINC code 74277-5 identifies "Mycobacterium tuberculosis stimulated gamma interferon CFP10 Ag spot count [#] in Blood". 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.
What does 74277-5 measure?
This code measures Mycobacterium tuberculosis stimulated gamma interferon.CFP10 Ag spot count in Bld. It belongs to the MICRO class in the LOINC classification.
What is LOINC?
LOINC (Logical Observation Identifiers Names and Codes) is a universal standard for identifying laboratory and clinical observations. It is maintained by the Regenstrief Institute and used worldwide for health data exchange.