title: Increased Synovial Fluid YKL-40 Levels are Linked with Symptomatic Severity in Knee Osteoarthritis Patients.
abstract: BACKGROUND
  Elevated serum and synovial fluid (SF) YKL-40 levels have been detected in knee osteoarthritis (OA) patients. The current study was focused on the correlation between YKL-40 levels in serum or SF and symptomatic severity in patients with knee osteoarthritis.
  
  
  METHODS
  144 patients with knee OA and 151 healthy individuals were recruited into this study. Symptomatic severity was determined using Western Ontario and McMaster Universities Arthritis Index (WOMAC) scores from OA patients. Serum and SF levels of YKL-40 were explored by enzyme-linked immunosorbent assay.
  
  
  RESULTS
  We found that YKL-40 levels in SF but not serum were independently and positively related to WOMAC pain (r = 0.531, p = 0.001), physical disability (r = 0.380, p = 0.025), and total scores (r = 0.407, p = 0.01) in knee OA patients.
  
  
  CONCLUSIONS
  YKL-40 in SF could represent a potential biomarker for assessing the symptomatic severity of OA.
authors.forename: Jian
authors.initials: J
authors.lastname: Guan
authors.forename: Zhang
authors.initials: Z
authors.lastname: Liu
authors.forename: Feng
authors.initials: F
authors.lastname: Li
authors.forename: Jian-Shu
authors.initials: JS
authors.lastname: Feng
authors.forename: Hua-Jun
authors.initials: HJ
authors.lastname: Wang
authors.forename: Jian-Guo
authors.initials: JG
authors.lastname: Chu
authors.forename: Yong-Zhou
authors.initials: YZ
authors.lastname: Song
authors.forename: Lei
authors.initials: L
authors.lastname: Xie
authors.forename: Luo-Bin
authors.initials: LB
authors.lastname: Ding
mesh_terms: D054392:Adipokines / Q000032:analysis* / Q000097:blood; D000368:Aged; D015415:Biomarkers / Q000032:analysis / Q000097:blood; D016022:Case-Control Studies; D002681:China; D000071451:Chitinase-3-Like Protein 1; D004185:Disability Evaluation; D004797:Enzyme-Linked Immunosorbent Assay; D005260:Female; D006801:Humans; D037102:Lectins / Q000032:analysis* / Q000097:blood; D008297:Male; D008875:Middle Aged; D020370:Osteoarthritis, Knee / Q000097:blood / Q000175:diagnosis / Q000378:metabolism*; D011237:Predictive Value of Tests; D012720:Severity of Illness Index; D013582:Synovial Fluid / Q000737:chemistry*; D015854:Up-Regulation
chemical_list: D054392:Adipokines; D015415:Biomarkers; C084533:CHI3L1 protein, human; D000071451:Chitinase-3-Like Protein 1; D037102:Lectins