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QuantiFERON TB-2G test for patients with active tuberculosis stratified by age groups
Yoshihiro Kobashi1, Keiji Mouri, Naoyuki Miyashita
1Division of Respiratory Diseases, Department of Medicine, Kawasaki Medical School, Kurashiki, Japan. yoshihiro@med.kawasaki-m.ac.jp
Scandinavian Journal of Infectious Diseases
|November 20, 2009
Summary
The QuantiFERON TB-2G (QFT-2G) test is a useful diagnostic tool for active tuberculosis (TB) in adults over 50, showing higher positive rates than the tuberculin skin test (TST), though indeterminate results increase with age.
Area of Science:
- Immunology
- Infectious Diseases
- Geriatrics
Background:
- Tuberculosis (TB) diagnosis relies on tests like the tuberculin skin test (TST) and interferon-gamma release assays.
- Age significantly impacts the sensitivity and specificity of TB diagnostic tests.
Purpose of the Study:
- To compare the effectiveness of the QuantiFERON TB-2G (QFT-2G) test and TST in diagnosing active TB across different age groups.
- To evaluate age-related performance variations in these TB diagnostic methods.
Main Methods:
- Retrospective analysis of QFT-2G and TST results in patients with active TB.
- Stratification of patient data by age in 10-year increments.
Main Results:
- TST positivity decreased significantly with age, particularly in individuals over 70.
- QFT-2G demonstrated higher positive rates than TST in adults over 50.
- Indeterminate QFT-2G results increased with age, potentially linked to underlying disease severity.
Conclusions:
- QFT-2G is a valuable supportive diagnostic tool for active TB in adults, outperforming TST in older populations.
- Age-related decline in TST response is notable, while QFT-2G maintains better sensitivity, despite increased indeterminate results in the elderly.
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