Clinical and biological parameters according to Lyme serology results
| Features | IgM+ | IgM− | p Value | IgG+ | IgG− | p Value | IgM+ and/or IgG+ | Not IgM+ and/or IgG+ | p Value | IgM+ and IgG+ | Not IgM+ and IgG+ | p Value |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Females, n/N (%) | 85/104 (81.7) | 536/706 | 0.21 | 43/62 (69.3) | 578/748 | 0.16 | 118/153 (77.1) | 503/657 (76.6) | 0.92 | 10/13 (76.9) | 611/797 (76.7) | 1* |
| Weight (kg), mean (SD) | 65 (11.7) | 68.7 (14.1) | 0.02 | 68.5 (14.3) | 68.2 (13.8) | 0.88 | 66.5 (13.0) | 68.6 (14.0) | 0.09 | 64.1 (10.1) | 68.3 (13.9) | 0.50 |
| Ritchie's index, mean (SD) | 17.9 (17.7) | 17.6 (17.2) | 0.56 | 24.3 (21.1) | 17.1 (17.1) | 0.002 | 19.9 (20.0) | 17.1 (16.8) | 0.19 | 24.5 (25.5) | 17.5 (17.3) | 0.29 |
| DAS28, mean (SD) | 5.2 (1.3) | 5.1 (1.3) | 0.78 | 5.4 (1.4) | 5.1 (1.3) | 0.05 | 5.2 (1.4) | 5.1 (1.3) | 0.26 | 5.5 (1.0) | 5.1 (1.3) | 0.15 |
| Lymphopenia <1000/mm³, n (%) | 9/104 (8.6) | 41/705 (5.8) | 0.26 | 7/62 (11.3) | 43/747 (5.8) | 0.09* | 13/153 (85.0) | 37/656 (5.6) | 0.19 | 3/13 (23.1) | 47/796 (5.9) | 0.04* |
| Neutrophils >7000/mm³, n (%) | 88/103 (85.4) | 606/697 (86.9) | 0.67 | 52/62 (83.9) | 642/738 (87.0) | 0.44 | 128/152 (84.2) | 566/648 (87.3) | 0.30 | 12/13 (92.3) | 682/787 (86.7) | 1* |
| ESR, mean (SD) | 33.8 (26.6) | 28.8 (24.3) | 0.05 | 30.9 (26.0) | 29.3 (24.5) | 0.86 | 32.7 (26.2) | 28.7 (24.2) | 0.09 | 32.9 (28.6) | 29.4 (24.6) | 0.74 |
| CRP (IU/L), mean (SD) | 19.1 (32.0) | 20.4 (32.5) | 0.30 | 22.8 (37.0) | 20.0 (32.0) | 0.30 | 20.2 (34.1) | 20.3 (32.0) | 0.44 | 23.3 (32.4) | 20.2 (32.4) | 0.84 |
| Serum creatinine >110 μmol/L, n/N (%) | 3/104 (2.9) | 14/694 (2.0) | 0.48* | 5/60 (8.3) | 12/738 (1.6) | 0.006* | 6/151 (4.0) | 11/647 (1.7) | 0.11* | 2/13 (15.4) | 15/785 (1.9) | 0.03* |
| RF (IU/L), mean (SD) | 94.1 (205.4) | 123.6 (583.8) | 0.01 | 117.3 (273.2) | 120.0 (567) | 0.84 | 106.7 (240.11) | 122.9 (599.7) | 0.02 | 57.3 (101.7) | 120.8 (554.3) | 0.65 |
| ACPA (IU/L), mean (SD) | 428.9 (1096.0) | 486.6 (1491.8) | 0.98 | 389.7 (935.4) | 486.6 (1481.2) | 0.37 | 440.5 (1072.8) | 488.2 (1521.0) | 0.88 | 104.9 (267.9) | 485.3 (1457.2) | 0.17 |
*By Fisher's exact test.
ACPA, anticitrullinated protein antibody; CRP, C reactive protein; DAS28, disease activity score on 28 joints; ESR, erythrocyte sedimentation rate; RF, rheumatoid factor.