Table 2.
Comparison of level and frequencies of positivity of autoantibodies according to presence of anti-MCV IgG
| Assay | Early RA (n = 33) | Established RA (n = 68) | ||
|---|---|---|---|---|
| MCV+ (n = 27) | MCV− (n = 6) | MCV+ (n = 60) | MCV− (n = 8) | |
| RF IgM+, n (%) | 16 (48.5) | 0 | 43 (63.2) | 0 |
| RF IgM, m (IQR)* | 27.2 (10.5–303.2) | 6.9 (2.3–12.3) | 66.8 (15.3–316.7) | 4.35 (0–21.9) |
| CCP2 +, n (%) | 13 (39.3) | 0 | 40 (58.8) | 0 |
| CCP2, m (IQR) * | 22.6 (4.1–2100.0) | 4.5 (3.2–7.1) | 163.7 (79–1772.0) | 3.8 (1.9–5.6) |
| CarbVIMIgM+, n (%) | 24 (72.7) | 5 (83.3) | 51 (75.0) | 6 (75.0) |
| CarbVIMIgM, m (IQR) | 63.6 (10.1–126.8) | 43.9 (25.2–97.7) | 55.1 (30.6–109.5) | 31.0 (20.7–65.6) |
| RF IgM−/CCP2−, n (%) | 10 (30.3) | 6 (100) | 15 (22.1) | 6 (75.0) |
| RF IgM +/CCP2 +, n (%) | 12 (36.4) | 0 | 38 (55.9) | 0 |
| RF IgM, IgG, IgA−/CCP2−, n (%) | 6 (18.2) | 5 (83.3) | 12 | 2 (25.0) |
| RF IgM, IgG, IgA +/CCP2 +, n (%) | 10 (30.3) | 0 | 27 (45.0) | 0 |
| RF IgM, IgG, IgA +/CCP2−, n (%) | 2 (6.1) | 0 | 4 (5.9) | 0 |
| CCP2−/CarbVIMIgG +/HC52 IgG +, n (%) | 1 (3.1) | 1 (16.7) | 10 (7, 16) | 2 (25.0) |
| CarbVIMIgM +/carbMCVIgM+, n (%) | 24 (72.7) | 5 (83.3) | 47 (69.1) | 5 (62.5) |
| CarbVIMIgM −/carbMCVIgM−, n (%) | 2 (6.1) | 0 | 9 (13.2) | 2 (25.0) |
| CarbVIMIgM +/carbMCVIgM +/RF IgM +/CCP2 +, n (%) | 12 (36.4) | 0 | 30 (44.1) | 0 |
RA rheumatoid arthritis, MCV mutated citrullinated vimentin, CarbVIM carbamylated vimentin, CarbMCV carbamylated mutated citrullinated vimentin, RF rheumatoid factor, CCP2 cyclic citrullinated peptides of second generation, Ig immunoglobulin, n number of patients, m median, IQR interquartile ranges
* Significant differences between anti-MCV IgG positive and negative groups on antibodies titers (p < 0.05)