title: Influence of replacing tuberculin skin test with ex vivo interferon γ release assays on decision to administer prophylactic antituberculosis antibiotics before anti-TNF therapy.
abstract: BACKGROUND
  The recommendations for detecting latent tuberculosis infection (LTBI) before antitumour necrosis factor (anti-TNF) therapy are based on the tuberculin skin test (TST), which lacks both specificity and sensitivity and can lead to unnecessary treatment with antibiotics. A study was undertaken to investigate the effect of replacing TST with interferon γ (IFNγ) release assays (IGRA) in screening for LTBI and deciding to begin prophylactic antituberculosis (TB) antibiotics before anti-TNF therapy in immune-mediated inflammatory diseases.
  
  
  METHODS
  In 15 tertiary care hospitals, consecutive patients with rheumatoid arthritis, spondylarthropathies or Crohn's disease were screened for LTBI before anti-TNF therapy with TST, QuantiFERON TB Gold in tube (QTF-Gold IT) and T-SPOT.TB at the same time. The potential diagnosis of LTBI and the effect on the decision to begin antibiotic prophylaxis were assessed.
  
  
  RESULTS
  Among 429 patients, 392 had results for the three tests. The results for TST, T-SPOT.TB and QTF Gold IT were positive for 35.2%, 15.1% and 9.9% of patients, respectively (p<0.0001). Antibiotics were required for 177 patients (45.2%) if positive TST results were included in the LTBI definition, 107 patients (27.3%) if TST results were replaced with results from one of the IGRA tests and 84 patients (21.4%) if TST results were replaced with QTF-Gold IT results (p<0.0001). The decision on the use of antibiotic prophylaxis was changed for 113 patients (28.8%, 95% CI 24.4% to 33.6%) if TST results were replaced with QTF-Gold IT results.
  
  
  CONCLUSIONS
  Replacing TST with IGRA for determining LTBI allowed the proportion of patients with immune-mediated inflammatory diseases needing prophylactic anti-TB antibiotics before beginning anti-TNF agents to be reduced by half.
authors.affiliation: Rhumatologie, Hôpital Bicêtre, Assistance Publique-Hôpitaux de Paris (AP-HP), Université Paris-Sud 11, INSERM U1012, 78 rue du Général Leclerc, Le Kremlin Bicêtre, France. xavier.mariette@bct.aphp.fr
authors.forename: Xavier
authors.initials: X
authors.lastname: Mariette
authors.forename: Gabriel
authors.initials: G
authors.lastname: Baron
authors.forename: Florence
authors.initials: F
authors.lastname: Tubach
authors.forename: Frédéric
authors.initials: F
authors.lastname: Lioté
authors.forename: Bernard
authors.initials: B
authors.lastname: Combe
authors.forename: Corinne
authors.initials: C
authors.lastname: Miceli-Richard
authors.forename: René-Marc
authors.initials: RM
authors.lastname: Flipo
authors.forename: Philippe
authors.initials: P
authors.lastname: Goupille
authors.forename: Matthieu
authors.initials: M
authors.lastname: Allez
authors.forename: Dominique
authors.initials: D
authors.lastname: Salmon
authors.forename: Dominique
authors.initials: D
authors.lastname: Emilie
authors.forename: Guislaine
authors.initials: G
authors.lastname: Carcelain
authors.forename: Philippe
authors.initials: P
authors.lastname: Ravaud
mesh_terms: D000328:Adult; D019072:Antibiotic Prophylaxis; D000911:Antibodies, Monoclonal / Q000627:therapeutic use; D001172:Arthritis, Rheumatoid / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy; D000075202:Contraindications; D003424:Crohn Disease / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy; D003657:Decision Making; D005260:Female; D006801:Humans; D059425:Interferon-gamma Release Tests; D055985:Latent Tuberculosis / Q000150:complications / Q000175:diagnosis* / Q000188:drug therapy; D008297:Male; D008403:Mass Screening / Q000379:methods*; D008875:Middle Aged; D011237:Predictive Value of Tests; D011364:Professional Practice; D055502:Secondary Prevention; D025242:Spondylarthropathies / Q000150:complications / Q000175:diagnosis / Q000188:drug therapy; D062606:Tertiary Care Centers; D014374:Tuberculin Test; D014409:Tumor Necrosis Factor-alpha / Q000037:antagonists & inhibitors
chemical_list: D000911:Antibodies, Monoclonal; D014409:Tumor Necrosis Factor-alpha