Anti-CCP antibodies are not a marker of severity in established rheumatoid arthritis: a magnetic resonance imaging study

A Narrative Literature Review Comparing the Key Features of Musculoskeletal Involvement in Rheumatoid Arthritis and Systemic Lupus Erythematosus

Although the clinical approach to the management of musculoskeletal manifestations in systemic lupus erythematosus (SLE) is often similar to that of rheumatoid arthritis (RA), there are distinct differences in immunopathogenesis, structural and imaging phenotypes and therapeutic evidence. Additionally, there are few published comparisons of these diseases. The objective of this narrative literature review is to compare the immunopathogenesis, structural features, magnetic resonance imaging (MRI) and musculoskeletal ultrasound (MSUS) studies and management of joint manifestations in RA and SLE. We highlight the key similarities and differences between the two diseases. Overall, the literature evaluated indicates that synovitis and radiographical progression are the key features in RA, while inflammation without swelling, tendinitis and tenosynovitis are more prominent features in SLE. In addition, the importance of defining patients with RA by the presence or absence of autoantibodies and categorizing patients with SLE by synovitis detected by musculoskeletal ultrasound and by structural phenotype (non-deforming, non-erosive arthritis, Jaccoud’s arthropathy and ‘Rhupus’) with respect to joint manifestations will also be discussed. An increased understanding of the joint manifestations in RA and SLE may inform evidence-based clinical decisions for both diseases.

A Study on Association Between Protein Carbonyl and Anti-cyclic Citrullinated Peptide Antibody in Rheumatoid Arthritis: Introducing a New Supplementary Biomarker

Redox state and immune mechanisms are two major factors implicated in rheumatoid arthritis (RA). Regarding some limitations of anti-cyclic citrullinated peptide (anti-CCP) antibody in RA diagnosis, recruiting another strong marker of oxidative stress could lead to more definitive diagnosis. To evaluate the potential of protein carbonyl content as a supplementary biomarker for RA. Eighty patients with RA attending the Research Center from 2015 to 2016 were recruited in this study. Smoker and alcoholic subjects, or those with any other systemic illness were excluded from the study. Demographic information and clinical data were collected. Numbers of swollen and tender joints were determined and RA disease activity was assessed. Serum samples were used for assessing protein carbonyl level, platelet count, and anti-CCP antibody values. Statistical analyses for significant differences were performed according to parametric (Student t test) and nonparametric (Mann-Whitney test) tests. The correlation was determined by Pearson coefficient. There was a significant correlation between protein carbonyl levels and anti-CCP antibodies in active RA (p value = 0.01), but not in remission phase (p value = 0.28). A significant positive correlation was observed between protein carbonyl levels and platelets count in active RA (p value = 0.001), but not in remission phase (p value = 0.85). Protein carbonyl could be considered as a future cost-effective supplementary biomarker, alongside anti-CCP antibody, in active RA diagnosis as it showed a significant positive correlation with anti-CCP antibody and platelet, two major mediators in the disease pathogenesis.

Diagnostic value of autoantibodies combined detection for rheumatoid arthritis

BACKGROUND

Rheumatoid arthritis (RA) is a chronic, inflammatory and autoimmune disease, there are many autoantibodies produced during disease progression in the patients' serum, and this work is to select a best detection scheme for RA diagnosis.

METHODS

Autoantibody levels including rheumatoid factor (RF), anti-cyclic citrullinated peptide (CCP), mutated citrullinated vimentin (MCV), anti-keratin antibodies(AKA), anti-perinuclear factor (APF), and Ig heavy chain binding protein (BIP), were measured, and the sensitivity, specificity, predictive values, accuracy, and Youden's index of different combining forms were all calculated in RA patients, disease, and healthy control group. The differences in the positive rates of the three groups were compared between any two of them.

RESULTS

Generally speaking, the sensitivity of the autoantibodies detected in parallel combination was higher than that in tandem, which was more specific. The sensitivity of anti-MCV and RF calculated in parallel (87.61%) was obviously better than that of anyone autoantibody (P<.05), and only increased slightly even if more autoantibodies were tested in parallel (P>.05). The specificity of anti-CCP and BIP measured in tandem (95.92%) was obviously higher than that of anyone autoantibody (P<.05). While increasing the detected number of autoantibody from two kinds to three or more, the specificity was improved insignificantly (P>.05).

CONCLUSION

Anti-BIP and CCP antibodies detected in tandem combination can obtain higher specificity, and have good clinical value for the differential diagnosis of RA.