title: Evaluation of interferon-gamma release assay (T-SPOT.TB(™) ) for diagnosis of tuberculosis infection in rheumatic disease patients.
abstract: OBJECTIVE
  Patients with rheumatic diseases are at higher risk of developing tuberculosis (TB). The objective of this prospective study was to evaluate the T-SPOT.TB assay (T cell enzyme-linked immuno-spot assay), for the diagnosis of tuberculosis infection in rheumatic disease patients in China.
  
  
  METHODS
  Prospectively enrolled patients came from the Department of Rheumatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine between July 2008 and Aug 2012 for TB screening. Subjects' histories of TB infection, previous TB contact or bacille Calmette-Guérin vaccination and concurrent immunosuppressive therapy, were reviewed carefully and recorded in detail. TST (tuberculin skin test) and TSPOT.TB assay were performed on the subjects. A prospective evaluation by Chi-square test was used for sensitivity and specificity of both TST and T-SPOT assay.
  
  
  RESULTS
  A total of 311 subjects included 114 (36.66%) male and 197 (63.34%) female subjects, with a median age of 37.7 ± 12.6 years (range 17-72). Thirty-two patients (10.29%) had a history of TB infection or previous TB contact; 256 patients (82.32%) were using glucocorticoids or immunosuppressants; 28 patients (9.0%) were clinically diagnosed as having TB infection. The sensitivity and specificity of TST for TB screening in rheumatic disease patients was 81.82% (9/11) and 67% (67/100), respectively. However, the sensitivity and specificity of T-SPOT assay was statistically higher at 92.86% (26/28) and 93.64% (265/283), respectively (P < 0.05).
  
  
  CONCLUSIONS
  As a new immunoassay for TB diagnosis, the sensitivity and specificity of T-SPOT is higher than TST. It is of great importance in the diagnosis of active or latent TB infection in rheumatic disease patients.
authors.affiliation: Department of Rheumatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Bin
authors.initials: B
authors.lastname: Jiang
authors.affiliation: Department of Rheumatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Huihua
authors.initials: H
authors.lastname: Ding
authors.affiliation: Department of Rheumatology, Ningbo First Hospital, Ningbo City, China.
authors.forename: Li
authors.initials: L
authors.lastname: Zhou
authors.affiliation: Department of Rheumatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Xiaoxiang
authors.initials: X
authors.lastname: Chen
authors.affiliation: Department of Rheumatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Sheng
authors.initials: S
authors.lastname: Chen
authors.affiliation: Department of Rheumatology, Renji Hospital, Shanghai Jiao Tong University School of Medicine, Shanghai, China.
authors.forename: Chunde
authors.initials: C
authors.lastname: Bao
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D018501:Antirheumatic Agents / Q000009:adverse effects*; D015415:Biomarkers / Q000378:metabolism; D016009:Chi-Square Distribution; D002681:China; D058501:Enzyme-Linked Immunospot Assay; D005260:Female; D005938:Glucocorticoids / Q000009:adverse effects*; D054884:Host-Pathogen Interactions; D006801:Humans; D016867:Immunocompromised Host; D007166:Immunosuppressive Agents / Q000009:adverse effects*; D007371:Interferon-gamma / Q000378:metabolism*; D059425:Interferon-gamma Release Tests; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000276:immunology*; D009894:Opportunistic Infections / Q000175:diagnosis* / Q000276:immunology / Q000382:microbiology; D011237:Predictive Value of Tests; D011446:Prospective Studies; D015203:Reproducibility of Results; D012216:Rheumatic Diseases / Q000188:drug therapy* / Q000276:immunology; D014374:Tuberculin Test; D014376:Tuberculosis / Q000175:diagnosis* / Q000276:immunology / Q000382:microbiology; D055815:Young Adult
chemical_list: D018501:Antirheumatic Agents; D015415:Biomarkers; D005938:Glucocorticoids; C573415:IFNG protein, human; D007166:Immunosuppressive Agents; D007371:Interferon-gamma
keywords: T cell enzyme-linked immuno-spot assay; rheumatic disease; sensitivity; specificity; tuberculosis