title: Diagnostic properties of metabolic perturbations in rheumatoid arthritis.
abstract: BACKGROUND
  The aim of this study was to assess the feasibility of diagnosing early rheumatoid arthritis (RA) by measuring selected metabolic biomarkers.
  
  
  METHODS
  We compared the metabolic profile of patients with RA with that of healthy controls and patients with psoriatic arthritis (PsoA). The metabolites were measured using two different chromatography-mass spectrometry platforms, thereby giving a broad overview of serum metabolites. The metabolic profiles of patient and control groups were compared using multivariate statistical analysis. The findings were validated in a follow-up study of RA patients and healthy volunteers.
  
  
  RESULTS
  RA patients were diagnosed with a sensitivity of 93% and a specificity of 70% in a validation study using detection of 52 metabolites. Patients with RA or PsoA could be distinguished with a sensitivity of 90% and a specificity of 94%. Glyceric acid, D-ribofuranose and hypoxanthine were increased in RA patients, whereas histidine, threonic acid, methionine, cholesterol, asparagine and threonine were all decreased compared with healthy controls.
  
  
  CONCLUSIONS
  Metabolite profiling (metabolomics) is a potentially useful technique for diagnosing RA. The predictive value was without regard to the presence of antibodies against cyclic citrullinated peptides.
authors.affiliation: Computational Life Science Cluster-CLiC, Department of Chemistry, Umeå University, SE-90187 Umeå, Sweden.
authors.forename: Rasmus K
authors.initials: RK
authors.lastname: Madsen
authors.forename: Torbjörn
authors.initials: T
authors.lastname: Lundstedt
authors.forename: Jon
authors.initials: J
authors.lastname: Gabrielsson
authors.forename: Carl-Johan
authors.initials: CJ
authors.lastname: Sennbro
authors.forename: Gerd-Marie
authors.initials: GM
authors.lastname: Alenius
authors.forename: Thomas
authors.initials: T
authors.lastname: Moritz
authors.forename: Solbritt
authors.initials: S
authors.lastname: Rantapää-Dahlqvist
authors.forename: Johan
authors.initials: J
authors.lastname: Trygg
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000175:diagnosis*; D005260:Female; D008401:Gas Chromatography-Mass Spectrometry; D006801:Humans; D008297:Male; D055432:Metabolomics / Q000379:methods*; D008875:Middle Aged; D012680:Sensitivity and Specificity; D055815:Young Adult