title: Diagnostic value of enzyme-linked immunospot assay using CFP10/ESAT6 fusion protein as antigen in spinal tuberculosis.
abstract: OBJECTIVE
  To establish a method of detecting spinal tuberculosis (TB) infection by enzyme-linked immunospot (ELlSPOT) assay and evaluate the value of CFP10/ESAT6 fusion protein for diagnosis of spinal TB.
  
  
  METHODS
  Suspected spinal TB patients were prospectively recruited in two hospitals (First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine; Nanfang Hospital, Southern Medical University) from May 2012 to December 2013. Data on clinical characteristics of the patients and conventional laboratory results were collected. Compare and analyze the positive detection rate in spinal TB diagnosis by different methods including ELISPOT detection and conventional detection methods.
  
  
  RESULTS
  47 patients with spinal TB had available biopsy or surgical specimens for histopathological examination and 41 specimens had pathological features consistent with a diagnosis of TB infection. Among the spinal TB patients and non-TB disease patients,the overall sensitivity, specificity, positive predictive value, and negative predictive value of the ELISPOT assay in spinal TB diagnosis were 82.7%,87.2%,89.6%, and 79.1%,respectively; the 4 indexes of the PPD skin test were 61.5%, 46.2%, 60.4%, and 47.4%, respectively;those of the antibody detection were 55.8%, 61.5%, 65.9%, and 51.1%. The positive rate of ELISPOT was significantly higher than those of PPD skin test and antibody detection test (82.7% vs. 61.5%, Χ² =5.786, P=0.016; 82.7% vs. 55.8%, Χ² =8.847, P=0.003), but not significantly different from the positive rate of pathological examination (82.7% vs. 87.2%, Χ² =0.396, P=0.529). Moderate agreement was found between pathological examination and the ELISPOT assay (87.2%, Κ=0.498, P=0.001).
  
  
  CONCLUSIONS
  With high sensitivity and specificity, the ELISPOT assay using CFP10/ESAT6 fusion protein as antigen is an effective technique for auxiliary diagnosis of spinal TB.
authors: Department of Spine Orthopedics, the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, Guangzhou 510405, China.
authors: Kai
authors: K
authors: Yuan
authors: Department of Spine Orthopedics, the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, Guangzhou 510405, China.
authors: De
authors: D
authors: Liang
authors: Army Tuberculosis Key Laboratory, Institute for Tuberculosis Research, the 309th.
authors: Xue-qiong
authors: XQ
authors: Wu
authors: Department of Spine Orthopedics, the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, Guangzhou 510405, China.
authors: Zhen-song
authors: ZS
authors: Yao
authors: Department of Spine Orthopedics, the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, Guangzhou 510405, China.
authors: Da-xiang
authors: DX
authors: Jin
authors: Department of Spine Orthopedics, the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, Guangzhou 510405, China.
authors: Zhi-dong
authors: ZD
authors: Yang
authors: Department of Spine Orthopedics, the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, Guangzhou 510405, China.
authors: Shun-cong
authors: SC
authors: Zhang
authors: Department of Spine Orthopedics, the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, Guangzhou 510405, China.
authors: Jin-yong
authors: JY
authors: Ding
authors: Department of Spine Orthopedics, the First Affiliated Hospital of Guangzhou University of Traditional Chinese Medicine, Guangzhou 510405, China.
authors: Xiao-bing
authors: XB
authors: Jiang
authors: Department of Spine Orthopedics, Nanfang Hospital, Southern Medical University, Guangzhou 510515, China.
authors: Jian-ting
authors: JT
authors: Chen
mesh_terms: D000941:Antigens; D058501:Enzyme-Linked Immunospot Assay; D006801:Humans; D011993:Recombinant Fusion Proteins; D014399:Tuberculosis, Spinal
chemical_list: D000941:Antigens; C505464:ESAT-6-CFP10 fusion protein; D011993:Recombinant Fusion Proteins