Serial testing for tuberculosis: Can we make sense of T cell assay conversions and reversions?
2007
Understanding T Cell Assay Changes in Tuberculosis Testing
publication
Evidence: low
Author Information
Author(s): Madhukar Pai, Richard O'Brien
Primary Institution: McGill University
Hypothesis
Can we make sense of T cell assay conversions and reversions in tuberculosis testing?
Conclusion
The study shows that T cell assay conversions and reversions frequently occur after Mycobacterium tuberculosis exposure.
Supporting Evidence
- IGRAs are more specific than TST and can be repeated without sensitization.
- Conversions and reversions occur with both IGRA and TST serial testing.
- Positive IGRA results vary more than negative results.
Takeaway
This study looks at how tests for tuberculosis can change over time, showing that results can go up and down even when someone is exposed to the bacteria.
Limitations
Existing studies do not provide strong evidence on the reproducibility of IGRAs and the interpretation of conversions and reversions.
Participant Demographics
The study involved exposed contacts in a high-prevalence country (The Gambia).
Digital Object Identifier (DOI)
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