Table 6.
Outcomes of juvenile myositis categorized by autoantibody
| Disease Course* |
Total (n=312) |
Anti-synthetase (n=15) |
Anti-SRP (n=6) |
Anti-Mi-2 (n=10) |
Anti-p155/140 (n=107) |
Anti-MJ (n=74) |
MSA and MAA Negative (n=100) |
Significant Differences† |
|---|---|---|---|---|---|---|---|---|
| Chronic | 161 (51.6) | 10 (66.7) | 6 (100.0) | 4 (40.0) | 70 (65.4) | 34 (45.9) | 37 (37.0) | SRP vs. None3 , MJ vs. p155/1401, p155/140 vs. None4 |
| Polycyclic | 74 (23.7) | 3 (20.0) | 0 (0.0) | 4 (40.0) | 24 (22.4) | 19 (25.7) | 24 (24.0) | |
| Monocyclic | 77 (24.7) | 2 (13.3) | 0 (0.0) | 2 (20.0) | 13 (12.1) | 21 (28.4) | 39 (39.0) |
| Total (N=374) | Anti-synthetase (n=19) |
Anti-SRP (n=6) | Anti-Mi-2 (n=11) | Anti-p155/140 (n=131) |
Anti-MJ (n=86) | MSA and MAA Negative (n=121) |
|||||||||
| n (%) | Miss- ing |
n (%) | Miss- ing |
n (%) | Miss- ing |
n (%) | Miss- ing |
n (%) | Miss- ing |
n (%) | Miss- ing |
n (%) | Miss- ing |
||
| Ever hospitalized |
191 (53.5) |
17 | 13 (68.4) |
0 | 6 (100.0) |
0 | 6 (54.5) |
0 | 58 (46.4) |
6 | 52 (62.7) |
3 | 56 (49.6) |
8 | SRP vs. p155/1403, SRP vs. None2, MJ vs. p155/1402 |
| Calcinosis | 120 (32.2) |
1 | 2 (10.5) |
0 | 0 (0.0) |
0 | 2 (18.2) |
0 | 40 (30.5) |
0 | 32 (37.2) |
0 | 44 (36.7) |
1 | Synth vs. MJ2, Synth vs. None2 |
| Wheelchair use | 64 (17.7) |
13 | 4 (22.2) |
1 | 5 (83.3) |
0 | 3 (27.3) |
0 | 19 (14.8) |
3 | 20 (23.8) |
2 | 13 (11.4) |
7 | Synth vs. SRP2, SRP vs. Mi-22, SRP vs. MJ3, SRP vs. p155/1404, SRP vs. None4, MJ vs. None2 |
| Mortality | 12 (3.4) |
18 | 3 (16.7.) |
1 | 0 (0.0) |
0 | 0 (0.0) |
1 | 3 (2.4) |
6 | 1 (1.3) |
6 | 5 (4.3) |
4 | Synth vs. MJ2, Synth vs. p155/1402 |
Abbreviations: SRP = signal recognition particle; MSA = myositis-specific autoantibodies; MAA = myositis-associated autoantibodies.
*
Total n for disease course differs because cases with an undefined disease course have been removed.
†
Significant differences
1
p < 0.05
2
p < 0.01
3
P < 0.005
4
p < 0.001
Abbreviations of autoantibodies: Synth = anti-synthetase; MJ = anti-MJ; p155/140 = anti-p155/140; SRP = anti-signal recognition particle; Mi-2 = anti-Mi-2.