title: Evaluation of the usefulness of interferon-gamma release assays and the tuberculin skin test for the detection of latent Mycobacterium tuberculosis infections in Korean rheumatic patients who are candidates for biologic agents.
abstract: OBJECTIVE
  The aim of this study was to evaluate the occurrence of active tuberculosis (TB) in patients who received both an interferon-gamma release assay (the QuantiFERON-TB Gold In-Tube test [QFT-GIT]) and tuberculin skin test (TST) in comparison with those who received QFT-GIT or TST alone for the detection of latent TB infection (LTBI).
  
  
  METHODS
  In total, 842 patients who received QFT-GIT or TST and used biologic agents between January 2007 and December 2012 were recruited to determine the usefulness of LTBI screening tests. The incidence of active TB was calculated relative to the LTBI screening method as the number of events per 100 000 person-years exposure.
  
  
  RESULTS
  TB occurred in two of the patients who complied with an LTBI prophylaxis strategy. The TB incidence in the group that received both QFT-GIT and TST was 151.05 (95% confidence interval [CI] 150.11-151.98)/100 000 person-years, and the incidence was 169.78 (95% CI 168.73-170.84)/100 000 person-years in the group that received only TST.
  
  
  CONCLUSIONS
  TB occurred even in some patients who received LTBI prophylaxis in compliance with national guidelines. The incidence of TB in patients who received either the QFT-GIT plus TST prophylaxis strategy or the TST prophylaxis strategy alone was higher than the annual incidence of the general population of the Republic of Korea. It is not possible to conclude which of the LTBI prophylaxis strategies is superior.
authors.affiliation: Division of Rheumatology, Department of Internal Medicine, Guro Hospital, Korea University College of Medicine, Seoul, Korea.
authors.forename: Jae-Hoon
authors.initials: JH
authors.lastname: Kim
authors.forename: Soyoung
authors.initials: S
authors.lastname: Won
authors.forename: Chan-Bum
authors.initials: CB
authors.lastname: Choi
authors.forename: Yoon-Kyoung
authors.initials: YK
authors.lastname: Sung
authors.forename: Gwan Gyu
authors.initials: GG
authors.lastname: Song
authors.forename: Sang-Cheol
authors.initials: SC
authors.lastname: Bae
mesh_terms: D000328:Adult; D018501:Antirheumatic Agents / Q000009:adverse effects / Q000627:therapeutic use*; D000995:Antitubercular Agents / Q000627:therapeutic use; D001688:Biological Products / Q000009:adverse effects / Q000627:therapeutic use*; D005260:Female; D006801:Humans; D016867:Immunocompromised Host; D015994:Incidence; D059425:Interferon-gamma Release Tests; D055985:Latent Tuberculosis / Q000175:diagnosis* / Q000188:drug therapy / Q000453:epidemiology / Q000276:immunology / Q000382:microbiology; D008297:Male; D008875:Middle Aged; D018579:Patient Selection; D011237:Predictive Value of Tests; D056910:Republic of Korea / Q000453:epidemiology; D012189:Retrospective Studies; D012216:Rheumatic Diseases / Q000175:diagnosis / Q000188:drug therapy* / Q000453:epidemiology / Q000276:immunology; D012307:Risk Factors; D013997:Time Factors; D016896:Treatment Outcome; D014374:Tuberculin Test
chemical_list: D018501:Antirheumatic Agents; D000995:Antitubercular Agents; D001688:Biological Products
keywords: QuantiFERON-TB Gold In-Tube test; biologic agent; interferon-gamma release assay; latent tuberculosis infection; tuberculin skin test