74279-1
LaboratoryGamma interferon negative control spot count [#] in Blood
Definition
The count of negative control spots (0 to >20) in a patient's T cells incubated without M. tuberculosis antigens (ESAT-6, CFP10). This term is created for, 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 test, a typical result is expected to have few to no spots in the negative (nil) control and 20 or more spots in the positive control (Mitogen stimulated). A negative control spot count of >10 is considered invalid.
LOINC 6-Axis Classification
Component
Gamma interferon.negative control spot count
Property
Num
Time Aspect
Pt
System
Bld
Scale Type
Qn
Method Type
N/A
Details
Class
MICRO
Order/Observation
Both
Short Name
IGNF neg cntrl Bld
Display Name
Gamma interferon negative control spot count (Bld) [#]
Related Names
Frequently Asked Questions
What is LOINC code 74279-1?
LOINC code 74279-1 identifies "Gamma interferon negative control spot count [#] in Blood". The count of negative control spots (0 to >20) in a patient's T cells incubated without M. tuberculosis antigens (ESAT-6, CFP10). This term is created for, 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 test, a typical result is expected to have few to no spots in the negative (nil) control and 20 or more spots in the positive control (Mitogen stimulated). A negative control spot count of >10 is considered invalid.
What does 74279-1 measure?
This code measures Gamma interferon.negative control 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.