1. To obtain an accurate result interpretation for a patient, combine only the results from tubes collected from the patient in the same sampling session. 2. Inaccurate or indeterminate results may occur if strict adherence to the LIAISON® QuantiFERON®-TB Gold Plus assay and QuantiFERON®-TB Gold Plus Blood Collection Tube instructions is not exercised. 3. Grossly hemolyzed, icteric or lipemic samples, as well as samples containing particulate matter or exhibiting obvious microbial contamination should not be tested. 4. Bacterial contamination or heat inactivation of the specimens may affect the test results. 5. The four individual blood collection tube results of a patient sample can be combined to determine the final qualitative interpretation only if assay testing of subsequent tube(s) occurs within ≤18 hours of testing of the initial tube, and all tubes are maintained at 2°-8°C prior to testing. 6. In order to ensure correct correlation of the result of each assay tube and the interpretation, a conversion factor must not be set on the LIAISON® XL Analyzer or LIAISON® XS Analyzer. 7. A negative result does not preclude the possibility of M. tuberculosis infection or tuberculosis disease: false-negative results can be due to the stage of infection (e.g., specimen obtained prior to the development of cellular immune response), co-morbid conditions that affect immune functions, incorrect handling of the blood collection tubes following venipuncture, incorrect performance of the assay, or other immunological variables. 8. A positive result should not be the sole or definitive basis for determining infection with M. tuberculosis. Incorrect performance of the assay may cause false-positive responses. 9. Heterophilic antibodies in human specimens can react with reagent immunoglobulins, interfering with in vitro immunoassays. Patients routinely exposed to animals or to animal serum products can be prone to this interference and their results should be evaluated with care. 10. While ESAT-6 and CFP-10 are absent from all BCG strains and from most known nontuberculous mycobacteria, it is possible that a positive result may be due to infection by M. kansasii, M. szulgai, or M. marinum. If such infections are suspected, alternative testing should be considered. 11. The performance characteristics of the test in the following groups of individuals has not been extensively evaluated: individuals younger than age 18 years, pregnant women, individuals with impaired or altered immune functions or other clinical conditions (e.g. HIV infection, transplant recipients, hematological disorders, malignancies, diabetes, chronic renal failure). | 
