The diagnostic utility of anti-cyclic citrullinated peptide antibodies, matrix metalloproteinase-3, rheumatoid factor, erythrocyte sedimentation rate, and C-reactive protein in patients with erosive and non-erosive rheumatoid arthritis.
OBJECTIVE
To compare the diagnostic utility of laboratory variables, including matrix metalloproteinase-3 (MMP-3), anticyclic citrullinated peptide (CCP) antibodies, rheumatoid factor (RF), erythrocyte sedimentation rate (ESR), and C-reactive protein (CRP) in patients with erosive and non-erosive rheumatoid arthritis (RA).


METHODS
We assembled a training set, consisting of 60 patients with RA, all fulfilling the revised criteria of the American College of Rheumatology. A commercial enzyme linked immunosorbent assay (ELISA) was used both to test for anti-CCP antibodies (second generation ELISA kit) and MMP; RF were detected by latex-enhanced immunonephelometric assay. CRP was measured by latex turbidimetric immunoassay.


RESULTS
The levels of anti-CCP antibody titers and ESR were significantly higher in patients with erosive disease than those in non-erosive RA patients (p < 0.001 and 0.0341) respectively. Moreover, a higher frequency of elevated titers of anti-CCP antibodies was found in RA patients with erosions compared to patients with non-erosive RA (78.3% vs. 43.2% respectively). The ROC curves of anti-CCP passed closer to the upper left corner than those other markers and area under the curve (AUC) of anti-CCP was significantly larger than AUC of other markers (0.755 for anti-CCP, 0.660 for ESR, 0.611 for CRP, 0.577 for RF, and 0.484 for MMP-3 female). A positive predictive value was higher for anti-CCP antibodies in comparison to other markers. We did not find significant statistical correlation between anti-CCP antibody titers and inflammatory markers such as ESR or CRP. However, we confirmed the correlation of elevated titers of anti-CCP antibodies and RF in both groups of patients whereas the degree of correlation was more significant in non-erosive patients.


CONCLUSIONS
The results of our study suggest that the presence of elevated anti-CCP antibody titers have better diagnostic performance than MMP-3, RF, CRP and ESR in patients with erosive RA.
Shovman
O
O
Center for Autoimmune Diseases, Department of Medicine B, Sheba Medical Center, Israel.
Gilburd
B
B
Zandman-Goddard
G
G
Sherer
Y
Y
Orbach
H
H
Gerli
R
R
Shoenfeld
Y
Y
D000368:Aged; D001172:Arthritis, Rheumatoid / Q000097:blood / Q000175:diagnosis* / Q000201:enzymology / Q000276:immunology*; D001323:Autoantibodies / Q000097:blood*; D015415:Biomarkers / Q000097:blood; D001799:Blood Sedimentation; D002097:C-Reactive Protein / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D019278:Matrix Metalloproteinase 3 / Q000097:blood; D008875:Middle Aged; D010456:Peptides, Cyclic / Q000276:immunology*; D011237:Predictive Value of Tests; D012217:Rheumatoid Factor / Q000097:blood; D012680:Sensitivity and Specificity
D001323:Autoantibodies; D015415:Biomarkers; D010456:Peptides, Cyclic; C487763:cyclic citrullinated peptide; D002097:C-Reactive Protein; D012217:Rheumatoid Factor; D019278:Matrix Metalloproteinase 3