Authors
M Pai, R Joshi, S Dogra, AA Zwerling, D Gajalakshmi, K Goswami, MVR Reddy, A Kalantri, PC Hill, D Menzies, PC Hopewell
Publication date
2009/1/1
Journal
The International journal of tuberculosis and lung disease
Volume
13
Issue
1
Pages
84-92
Publisher
International Union Against Tuberculosis and Lung Disease
Description
BACKGROUND
Interferon-gamma assays (IGRAs) are alternatives to the tuberculin skin test (TST), but IGRA conversions and reversions are not well understood. In a pilot study, we determined conversions and reversions using QuantiFERON-TB Gold In-Tube® (QFT) among household contacts of TB cases, and evaluated the effect of using various definitions and criteria for conversions.
DESIGN
In a cohort of 250 contacts in India, 46% were TST-positive at baseline and 54% were QFT-positive. We re-tested this cohort after 12 months. Conversion rates were estimated using several definitions.
RESULTS
Of the 250 contacts, 205 (82%) underwent repeat testing. Among 85 contacts with baseline TST-negative/QFT-negative results, TST conversion rates ranged between 7.5% and 13.8%, and QFT conversion rates ranged between 11.8% and 21.2%, depending on the definitions used. Among 109 contacts who were …
Total citations
Scholar articles
M Pai, R Joshi, S Dogra, AA Zwerling, D Gajalakshmi… - The International journal of tuberculosis and lung …, 2009