Table 3.
Clinical Features of Juvenile Myositis Patients with Anti-HMGCR Autoantibodies Compared to those with other Myositis Autoantibodies.
| Feature | Anti-HMGCR (n=5), N (%) |
Anti-SRP (n=8), N (%) |
Anti-Synthetase (n=16), N (%) |
Anti-p155/140 (n=142), N (%) |
Anti-MJ (n=111), N (%) |
MSA and MAA negative (n=62), N (%) |
|
|---|---|---|---|---|---|---|---|
| Musculoskeletal | Proximal weakness | 5 (100) | 7 (100) | 16 (100) | 141 (99.3) | 110 (99.1) | 62 (100) |
| Distal weakness | 5 (100) | 7 (100) | 5 (31.3) | 63 (45.7) | 51 (47.7) | 27 (43.6) | |
| Falling episodes | 5 (100) | 7 (100) | 4 (26.7) | 52 (36.9) | 54 (49.1) | 26 (42.6) | |
| Muscle atrophy | 5 (100) | 6 (85.7) | 5 (33.3) | 55 (39.0) | 37 (33.6) | 17 (28.3) | |
| Myalgia | 2 (40.0) | 3 (42.9) | 11 (73.3) | 79 (57.7) | 81 (74.3) | 35 (58.3) | |
| Asymmetric weakness | 1 (20.0) | 3 (42.9) | 1 (6.3) | 17 (12.1) | 21 (19.1) | 5 (8.5) | |
| Muscle cramps | 0 (0) | 1 (14.3) | 2 (12.5) | 21 (15.3) | 38 (34.9) | 15 (25.9) | |
| Arthralgia | 5 (100) | 2 (28.6) | 13 (81.3) | 80 (56.3) | 74 (66.7) | 33 (54.1) | |
| Contractures | 5 (100) | 4 (57.1) | 6 (40.0) | 85 (59.9) | 68 (61.8) | 32 (51.6) | |
| Arthritis | 2 (40.0) | 3 (42.9) | 11 (68.8) | 63 (44.4) | 52 (47.3) | 28 (45.2) | |
| Cutaneous | Gottron’s papules | 3 (60.0) | 0 (0) | 9 (56.3) | 137 (96.5) | 88 (79.3) | 48 (78.7) |
| Heliotrope rash | 3 (60.0) | 0 (0) | 12 (75.0) | 128 (90.1) | 90 (81.1) | 43 (70.5) | |
| Periungual capillary abn. | 3 (60.0) | 4 (57.1) | 11 (68.8) | 123 (87.9) | 82 (75.2) | 35 (60.3) | |
| Malar rash | 3 (60.0) | 0 (0) | 5 (31.3) | 131 (92.3) | 75 (67.6) | 34 (55.7) | |
| Linear extensor erythema | 3 (60.0) | 0 (0) | 3 (18.8) | 72 (51.4) | 24 (22.2) | 18 (30.0) | |
| “V-sign” or Shawl Rash | 2 (40.0) | 0 (0) | 4 (25.0) | 68 (48.2) | 25 (22.5) | 17 (27.9) | |
| Raynaud phenomenon | 0 (0) | 4 (57.1) | 5 (31.3) | 13 (9.2) | 4 (3.6) | 8 (13.1) | |
| “Mechanic’s hands” | 0 (0) | 1 (14.3) | 5 (31.3) | 7 (5.0) | 2 (1.8) | 3 (4.9) | |
| Gastrointestinal | Dysphagia | 3 (60.0) | 4 (57.1) | 3 (18.8) | 54 (38.0) | 58 (52.3) | 21 (34.4) |
| Regurgitation | 3 (60.0) | 1 (14.3) | 3 (18.8) | 29 (20.4) | 29 (26.4) | 8 (12.9) | |
| Cardiopulmonary | Abnormal PFT | 2 (40.0) | 6 (85.7) | 10 (76.9) | 23 (23.5) | 20 (24.1) | 8 (16.7) |
| Interstitial lung disease | 0 (0) | 0 (0) | 11 (68.8) | 3 (2.1) | 2 (1.8) | 3 (4.9) | |
| Abnormal EKG or ECHO | 1 (20.0) | 4 (57.1) | 3 (21.4) | 12 (11.1) | 11 (12.0) | 11 (21.6) | |
| Constitutional | Weight loss | 4 (80.0) | 5 (71.4) | 10 (62.5) | 49 (34.5) | 36 (32.7) | 19 (31.7) |
| Fever | 2 (40.0) | 1 (14.3) | 11 (68.8) | 42 (29.6) | 42 (37.8) | 27 (44.3) | |
| Adenopathy | 2 (40.0) | 0 (0) | 3 (18.8) | 30 (21.4) | 22 (20.2) | 10 (16.7) |
Abbreviations: hydroxy-3-methylglutaryl-coenzyme A reductase; SRP, signal recognition particle; ARS, anti-synthetase; p155/140, transforming inhibitory factor-1, TIF-1; MSA, myositis-specific autoantibodies; MAA, myositis-associated autoantibodies; Ab, autoantibodies; PFT, pulmonary function testing; EKG, electrocardiogram; ECHO, echocardiogram. Note that PFTs and EKG/ECHO were missing in 12 – 31% of patients.