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Updated: May 4, 2026
An In Vitro Model for Measuring Immune Responses to Malaria in the Context of HIV Co-infection
Published on: October 6, 2015
Low prevalence of positive interferon-gamma tests in HIV-positive long-term immigrants in Norway
N D Pullar1, H Steinum2, K Tonby3
1Department of Internal Medicine, Section for Infectious Diseases, University Hospital of Northern Norway, Tromsø, Norway; Department of Clinical Medicine, Faculty of Health Sciences, University of Tromsø, Tromsø, Norway.
Objective:
To determine the prevalence and predictors of positive interferon-gamma release assays (IGRAs) and tuberculin skin tests (TSTs) in human immunodeficiency virus (HIV) infected patients in Norway, a low tuberculosis (TB) endemic country.
Design:
Multicentre cross-sectional study of 298 HIV patients tested with QuantiFERON®-TB Gold In-Tube (QFT-GIT), T-SPOT®.TB (T-SPOT) and TST.
Results:
A total of 77/298 (26%) QFT-GIT, 29/117 (25%) T-SPOT and 52/217 (24%) TSTs (≥ 5 mm) were positive. The median CD4 count was 427 cells/l. Three QFT-GIT results but no T-SPOT results were indeterminate. Of 52 TST-positive patients, 34 (65%) were QFT-GIT-positive (median interferon-gamma [IFN-] 4.38 international units [IU]/ml), compared to 16% of the TST-negative patients (median INF- 0.81 IU/ml, P < 0.001). Origin from a TB-endemic country, previous active TB and TB exposure were associated with a positive QFT-GIT (P 0.01). Patients from TB-endemic countries living in Norway for ≥ 10 years had lower odds of a positive QFT-GIT (12%; OR 0.17, 95%CI 0.060.53, P 0.002) than patients with 03 years' residence (49%).
Conclusion:
The prevalence of positive IGRAs in HIV-infected patients was high in this low TB endemic setting. Lower QFT-GIT positivity in long-term residents from TB-endemic countries may reflect a waning of TB-specific immune responses.
