title: [Value of four serum markers in the diagnosis of rheumatoid arthritis].
abstract: OBJECTIVE
  To systematically evaluate the values of 4 serum markers in the diagnosis of rheumatoid arthritis (RA).
  
  
  METHODS
  Serum samples were obtained from 278 RA patients and 510 control subjects and the levels of rheumatoid factor (RF), anticyclic citrullinated peptide antibody (CCP), antikeratin antibody (AKA), and glucose-6-phosphate isomerase (GPI) were detected using immune turbidimetry, ELISA, indirect immunofluorescence, and ELISA, respectively. The values of these 4 serum markers and their combinations in RA diagnosis were systemically assessed.
  
  
  RESULTS
  In RA diagnosis using one serum marker, two markers, and three or four markers, RF, RF+CCP, RF+CCP+GPI, respectively, had the highest sensitivity; CCP, CCP+AKA, and RF+CCP+AKA+GPI, respectively, had the highest specificity; CCP, CCP+GPI, and RF+CCP+AKA+GPI, respectively, had the highest positive predictive value; GPI, RF+CCP, and RF+CCP+GPI, respectively, had the highest negative predictive value; CCP, CCP+GPI, and RF+CCP+AKA+GPI, respectively, had the highest positive likely ratio; GPI, RF+CCP, and RF+CCP+GPI, respectively, had the lowest negative likely ratio.
  
  
  CONCLUSIONS
  CCP, RF+CCP, and RF+CCP+GPI are the most ideal for RA diagnosis using one, two, and three or more markers, respectively. CCP is the essential marker for RA diagnosis, and a combined detection of the serum makers can significantly improve the diagnostic accuracy.
authors: First Department of Rheumatology and Immunology, Shengjing Hospital Affiliated to China Medical University, China. zxgcmu@163.com
authors: Xingang
authors: X
authors: Zhang
authors: Li
authors: L
authors: Jiang
authors: Xiaoli
authors: X
authors: Zhang
authors: Yun
authors: Y
authors: Guo
authors: Tao
authors: T
authors: Shen
authors: Xiaofei
authors: X
authors: Wang
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001172:Arthritis, Rheumatoid / Q000097:blood* / Q000175:diagnosis*; D001323:Autoantibodies / Q000097:blood; D015415:Biomarkers / Q000097:blood*; D016022:Case-Control Studies; D002956:Citrulline / Q000276:immunology; D005260:Female; D005956:Glucose-6-Phosphate Isomerase / Q000097:blood; D006801:Humans; D007633:Keratins / Q000276:immunology; D008297:Male; D008875:Middle Aged; D012217:Rheumatoid Factor / Q000097:blood; D055815:Young Adult
chemical_list: D001323:Autoantibodies; D015415:Biomarkers; D002956:Citrulline; D007633:Keratins; D012217:Rheumatoid Factor; D005956:Glucose-6-Phosphate Isomerase