title: Low prevalence of positive interferon-gamma tests in HIV-positive long-term immigrants in Norway.
abstract: 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.
  
  
  METHODS
  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%).
  
  
  CONCLUSIONS
  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.
authors.affiliation: Department 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.
authors.forename: N D
authors.initials: ND
authors.lastname: Pullar
authors.affiliation: Department of Infectious Diseases, Trondheim University Hospital, Trondheim, Norway.
authors.forename: H
authors.initials: H
authors.lastname: Steinum
authors.affiliation: Department of Infectious Diseases, Oslo University Hospital (Ullevål), Nydalen, Oslo, Norway; Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway.
authors.forename: K
authors.initials: K
authors.lastname: Tonby
authors.affiliation: Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway; Section for Clinical Immunology and Infectious Diseases, Oslo University Hospital (Rikshospitalet), Nydalen, Oslo, Norway; Department of Medicine, Drammen Hospital, Vestre Viken Hospital Trust, Drammen, Norway.
authors.forename: L
authors.initials: L
authors.lastname: Heggelund
authors.affiliation: Department of Medicine, Haukeland University Hospital, Bergen, Norway.
authors.forename: R A
authors.initials: RA
authors.lastname: Leiva
authors.affiliation: Department of Internal Medicine, Haugesund Hospital, Haugesund, Norway.
authors.forename: R
authors.initials: R
authors.lastname: Ofstad
authors.affiliation: Department 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.
authors.forename: J N
authors.initials: JN
authors.lastname: Bruun
authors.affiliation: Department of Infectious Diseases, Oslo University Hospital (Ullevål), Nydalen, Oslo, Norway; Institute of Clinical Medicine, Faculty of Medicine, University of Oslo, Oslo, Norway; Department of Medicine, Haukeland University Hospital, Bergen, Norway; and Department of Clinical Science, University of Bergen, Bergen, Norway.
authors.forename: A M
authors.initials: AM
authors.lastname: Dyrhol-Riise
mesh_terms: D000328:Adult; D000368:Aged; D018791:CD4 Lymphocyte Count; D060085:Coinfection; D003430:Cross-Sectional Studies; D054242:Emigrants and Immigrants; D004641:Emigration and Immigration; D019353:Endemic Diseases; D005260:Female; D015658:HIV Infections / Q000175:diagnosis* / Q000208:ethnology* / Q000276:immunology; D006801:Humans; D059425:Interferon-gamma Release Tests / Q000379:methods; D008297:Male; D008875:Middle Aged; D009664:Norway / Q000453:epidemiology; D011237:Predictive Value of Tests; D015995:Prevalence; D012307:Risk Factors; D013997:Time Factors; D014374:Tuberculin Test; D014376:Tuberculosis / Q000175:diagnosis* / Q000208:ethnology* / Q000276:immunology / Q000382:microbiology; D055815:Young Adult