Skip to main content

Table 2 Muscle disease in those with anti-MDA5

From: Anti-MDA5 autoantibodies in juvenile dermatomyositis identify a distinct clinical phenotype: a prospective cohort study

  Anti-MDA5 autoantibody-positive Anti-MDA5 autoantibody-negative
Muscle strength
Median lowest ever recorded CMAS (IQR)a   46 (38 to 52) 40 (27 to 48)
Muscle histology  
Median biopsy score (IQR) (17)b Inflammatory (0 to 12)c 2 (2 to 4.8) 7 (5.5 to 9.5)
Vascular (0 to 3)c 0 (0 to 0) 1 (0 to 2)
Muscle fibre (0 to 10)c 2 (1, 2) 7 (4 to 9)
Connective tissue (0 to 2)c 0 (0 to 0) 1 (0 to 1)
Total (0 to 27) c 4 (3.25 to 8.5) 15 (12.5 to 21)
  VAS severity (0 to 10) c 2 (2) 5 (3.6 to 8)
  1. a.P = 0.03; bbiopsies were analysed from 11 patients with anti-MDA5 autoantibodies and 30 without; cP <0.005. Patients with anti-MDA5 had less muscle involvement, both clinically, as measured by the childhood myositis assessment score (CMAS) and histologically, as quantified by the juvenile dermatomyositis (JDM) muscle biopsy scoring tool. VAS, visual analogue scale.