title: Efficacy of inducible protein 10 as a biomarker for the diagnosis of tuberculosis.
abstract: OBJECTIVE
  This study evaluated inducible protein 10 (IP-10) as a diagnostic biomarker for specific tuberculosis (TB) infection and evaluated the ability of IP-10 to distinguish between active TB and latent TB infection (LTBI).
  
  
  METHODS
  Forty-six patients with active pulmonary TB, 22 participants with LTBI, and 32 non-TB controls were enrolled separately. We measured IP-10 in serum and in supernatants from whole blood stimulated with TB-specific antigens.
  
  
  RESULTS
  TB antigen-dependent IP-10 secretion was significantly increased in the active TB patients and LTBI subjects compared with controls, but did not differ significantly between the active TB patients and LTBI subjects. Serum IP-10 levels were higher in active TB than in LTBI (174.9 vs. 102.7pg/ml, p=0.002). The respective rates of positive responders of TB antigen-dependent IP-10 were 97.8%, 90.9%, and 12.5% in active TB, LTBI, and non-TB controls, respectively. For serum IP-10, 87.5%, 45.5%, and 9.5% of responders were positive in the respective groups.
  
  
  CONCLUSIONS
  The IP-10 response to TB antigen may constitute a specific biomarker for TB infection, but does not by itself distinguish between active TB and LTBI. Serum IP-10 may enhance the diagnostic performance when used in combination with another marker.
authors.affiliation: Division of Pulmonology, Department of Internal Medicine, Yonsei University College of Medicine, 50 Yonseiro, Seodaemun-gu, Seoul 120-752, Republic of Korea.
authors.forename: Ji Young
authors.initials: JY
authors.lastname: Hong
authors.forename: Gyeong Seo
authors.initials: GS
authors.lastname: Jung
authors.forename: Hyunjung
authors.initials: H
authors.lastname: Kim
authors.forename: Young Mi
authors.initials: YM
authors.lastname: Kim
authors.forename: Hye Jon
authors.initials: HJ
authors.lastname: Lee
authors.forename: Sang-Nae
authors.initials: SN
authors.lastname: Cho
authors.forename: Se Kyu
authors.initials: SK
authors.lastname: Kim
authors.forename: Joon
authors.initials: J
authors.lastname: Chang
authors.forename: Young Ae
authors.initials: YA
authors.lastname: Kang
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood*; D016022:Case-Control Studies; D054357:Chemokine CXCL10 / Q000097:blood*; D003937:Diagnosis, Differential; D005260:Female; D006801:Humans; D055985:Latent Tuberculosis / Q000097:blood / Q000175:diagnosis*; D008297:Male; D008875:Middle Aged; D009169:Mycobacterium tuberculosis / Q000276:immunology; D011237:Predictive Value of Tests; D056910:Republic of Korea; D014374:Tuberculin Test; D014397:Tuberculosis, Pulmonary / Q000097:blood / Q000175:diagnosis*; D055815:Young Adult
chemical_list: D015415:Biomarkers; C114753:CXCL10 protein, human; D054357:Chemokine CXCL10