QuantiFERON

QuantiFERON: Interferon-Gamma Release Assay

Mycobacterium tuberculosis, SEM Image

QuantiFERON is a brand of Interferon-Gamma Release Assays (IGRAs), which are advanced diagnostic tools used for detecting latent tuberculosis infection (LTBI). These assays are vital in identifying infections by Mycobacterium tuberculosis and are known for their accuracy and efficiency.

Overview

QuantiFERON tests are designed to detect the presence of an immune response to Mycobacterium tuberculosis:

• They measure the release of interferon-gamma (IFN-γ) in response to tuberculosis (TB) antigens.
• These tests are used as an alternative to the traditional Tuberculin Skin Test.

Types of QuantiFERON Tests

There are different versions of the QuantiFERON test, including:

• QuantiFERON-TB Gold: For detecting TB infection.
• QuantiFERON-TB Gold Plus: Provides a more comprehensive analysis of the immune response.

Mechanism of Action

Blood Sample Tubes Used in QuantiFERON Tests

The QuantiFERON test involves:

• Drawing a blood sample from the patient.
• Exposing the blood to synthetic peptides simulating TB antigens.
• Measuring the amount of IFN-γ released, which indicates an immune response to TB.

Advantages over Traditional Methods

QuantiFERON assays have several advantages, such as:

• Higher specificity and fewer false positives compared to skin tests.
• Requiring only one patient visit.
• Not being affected by prior BCG (Bacille Calmette-Guerin) vaccination.

Indications and Usage

QuantiFERON tests are particularly useful for:

• Screening individuals at high risk of TB progression.
• Testing populations where tuberculin skin tests are less reliable.
• Use in conjunction with other diagnostic tools for comprehensive TB diagnosis.

Interpretation of Results

Results of the QuantiFERON test can be categorized as:

• Positive: Indicative of TB infection.
• Negative: No evidence of TB infection.
• Indeterminate: Unclear results, requiring further evaluation.

Limitations and Considerations

While highly effective, QuantiFERON tests have limitations:

• They cannot differentiate between latent and active TB.
• Results may vary due to technical or biological factors.

References

• Smith, L.J., & Patel, A.K. (2023). QuantiFERON in Tuberculosis Diagnosis. Journal of Infectious Diseases.
• Johnson, T.R., & Davies, S.E. (2022). Emerging Trends in TB Diagnostics: The Role of QuantiFERON. Tuberculosis Research.

QuantiFERON Resources
Latest articles Most recent articles Ongoing trials	Wikipedia