Table 4.
Pathology features in muscle biopsies from JDM patients with Mi2, NXP2 and MDA5 autoantibodies
| Histology | Mi2 (n = 4) | NXP2 (n = 4) | MDA5 (n = 2) |
p value K-W1 |
p value M-W2 |
|---|---|---|---|---|---|
| CD3 endomysial (0/1/2) | 3/1/0 | 2/2/0 | 2/0/0 | 0.4720 | 0.5357 |
| CD3 perimysial (0/1/2) | 1/0/3 | 1/0/3 | 2/0/0 | 0.1850 | 1.0000 |
| CD3 perivascular (0/1/2) | 0/1/3 | 1/0/3 | 2/0/0 | 0.1083 | 0.8687 |
| Macrophages endomysial (0/1/2) | 0/0/4 | 0/3/1 | 1/1/0 | 0.0377 | 0.0632 |
| Macrophages perimysial (0/1/2) | 0/1/3 | 0/3/1 | 1/1/0 | 0.1136 | 0.2248 |
| Macrophages perivascular (0/1/2) | 1/2/1 | 0/3/1 | 2/0/0 | 0.1228 | 0.6446 |
| Capillary TRI (EM) (0/1/2) | 0/1/2 | 0/0/4 | 2/0/0 | 0.0970 | 0.3778 |
| Arterial abnormal (0/1) | 0/4 | 1/3 | 2/0 | 0.0554 | 0.4497 |
| Infarction (0/1) | 4/0 | 3/1 | 2/0 | 0.4724 | 0.4497 |
| MHC-1 upregulation (0/1) | 0/4 | 0/3 | 1/1 | 0.1738 | 1.0000 |
| Atrophy perifascicular (0/1/2) | 0/1/3 | 0/1/3 | 2/0/0 | 0.0601 | 1.0000 |
| Atrophy non-perifascicular (0/1) | 2/2 | 3/1 | 2/0 | 0.4724 | 0.5357 |
| Type IIc fibers (0/1) | 1/3 | 1/3 | 2/0 | 0.1850 | 1.0000 |
| Degeneratinga fibers perifascicular (0/1/2) | 0/1/3 | 0/3/1 | 2/0/0 | 0.0498 | 0.2248 |
| Degeneratinga fibers non-perifascicular (0/1/2 | 2/1/1 | 1/2/1 | 2/0/0 | 0.3221 | 0.6612 |
| Internal nuclei (0/1) | 2/2 | 3/1 | 2/0 | 0.4724 | 0.5357 |
| Fibrosis endomysial (0/1) | 2/2 | 3/1 | 2/0 | 0.4724 | 0.5357 |
| Fibrosis perimysial (0/1) | 1/3 | 1/3 | 2/0 | 0.1850 | 1.0000 |
| ALK perimysium (0/1/2) | 0/1/3 | 3/1/0 | 2/0 | 0.0271 | 0.0284 |
| C5b-9 myofiber (0/1/2) | 0/0/3 | 1/3/0 | 2/0/0 | 0.0219 | 0.0308 |
| C5b-9 capillary (0/1/2) | 2/1/0 | 0/0/4 | 2/0/0 | 0.0180 | 0.0277 |
1: p-values calculated by Kruskal-Wallis test among the Mi-2, NXP-2 and MDA5 mono-autoantibody groups. Patients with multiple autoantibodies were excluded
2: p-values calculated by Mann-Whitney test between the Mi-2 and NXP-2 mono-autoantibody groups. Patients with multiple autoantibodies were excluded
a: These include degenerating fibers, regenerating fibers and necrotic fibers