Seasonal variation in the performance of QuantiFERON-TB Gold In-Tube assays used for the diagnosis of tuberculosis infection. (May 2018)

• Record Type: Journal Article
• Authors: Tebruegge, Marc; Curtis, Nigel; Clifford, Vanessa; Fernandez-Turienzo, Cristina; Klein, Nigel; Fidler, Katy; Mansour, Salah; Elkington, Paul; Morris-Jones, Stephen
• Is Part Of: Tuberculosis. Volume 110(2018)
• Page Start: 26
• Page End: 29
• Publication Date: 2018-05
• Subjects: Tuberculosis -- Interferon-gamma release assay -- Performance -- Indeterminate -- Seasonality; 616.995
• DOI: 10.1016/j.tube.2018.03.002
• Languages: English
• ISSNs: 1472-9792

Abstract

Abstract: This study aimed to determine whether there are seasonal changes in the performance of QuantiFERON-TB Gold In-Tube (QFT-GIT) assays, an interferon-gamma release assay widely used for the diagnosis of tuberculosis infection. Results of 31, 932 QFT-GIT assays performed at a large independent, accredited diagnostic service provider in London, UK over a 4.5-year-period were analysed. The proportion of positive results was significantly lower in autumn (14.8%) than in spring (16.0%; p = 0.0366) and summer (17.5%; p < 0.0001), but similar to winter (15.2%; p = 0.4711). The proportion of indeterminate results was significantly higher in autumn (8.2%) than in spring (6.2%; p < 0.0001), summer (4.8%; p < 0.0001), and winter (6.2%; p < 0.0001). The highest proportions of indeterminate results were observed in October (8.4%) and November (8.8%), the lowest in June (4.5%). Our data show that significant seasonal variation occurs in the performance of QFT-GIT assays in a temperate climate setting. Potential underlying mechanisms, including host and environmental factors, are discussed.