How do you interpret QuantiFERON TB Gold results?
The QuantiFERON(R) TB Gold (in Tube) assay is intended for use as an aid in diagnosis of TB infection. Negative results suggest that there is not TB infection. In patients with high suspicion of exposure, a negative test should be repeated. A positive test indicates infection with Mycobacterium tuberculosis.
What is a normal QuantiFERON TB Gold?
The QuantiFERONR TB Gold Plus (in Tube) assay is intended for use as an aid in diagnosis of TB infection….
| Components | Reference Interval |
|---|---|
| QuantiFERON-TB Gold In-Tube | Negative |
| QuantiFERON-TB1 minus NIL | 0.34 IU/mL or less |
| QuantiFERON-TB2 minus NIL | 0.34 IU/mL or less |
| QuantiFERON MITOGEN minus NIL | No reference interval |
How do you read a QuantiFERON test?
How are QFT-Plus results interpreted?
- Positive – suggests that TB infection is likely.
- Negative – suggests that TB infection is unlikely.
- Indeterminate – suggests the need for further investigations or repeat testing.
What is normal range for TB blood test?
Quantiferon-TB Gold Plus (QFT-Plus) is an interferon gamma release assay used to diagnose latent tuberculosis (LTB). A borderline range (0.20 to 0.99 IU/ml) around the cutoff (0.35 IU/ml) has been suggested for the earlier QFT version.
Is QuantiFERON gold always positive?
After three months 87.5% were still QFT-TB positive (35/40 tested) whereas after 15 months, one year after the end of therapy, 84.6% remained positive (22/26 tested). All patients with reversed QFT-TB test after three months were still negative at 15 months.
What is the normal range for tuberculosis?
In a healthy person whose immune system is normal, induration greater than or equal to 15 mm is considered a positive skin test. If blisters are present (vesiculation), the test is also considered positive. In some groups of people, the test is considered positive if induration less than 15 mm is present.
What is a normal Mitogen nil result?
Mitogen-Nil The maximum non-specific stimulated interferon- gamma level that may be produced by the patient’s lymphocytes minus the Nil (i.e., basal) level of interferon-gamma. (The reporting range for the Nil is 0 – >8.0. The reporting range for the Tb Antigen-Nil and Mitogen-Nil is 0 – >10 IU/mL.)
How accurate is Quantiferon gold test?
The overall sensitivity for active TB was 87.5%, ranging from 62.5% in children 25–36 months old to 100% in children older than 49 months. The overall specificity for active TB was 93.6%.