Table 1

Sensitivity and specificity of anti-cN-1A autoantibodies

SeraNumberAnti-cN-1A reactivity*
nPer cent
Inclusion body myositis2388837
Polymyositis/scleroderma overlap1200
Neuromuscular diseases9344
Sjögren's syndrome22836
Systemic lupus erythematosus44920
Rheumatoid arthritis4412
Multiple sclerosis4025
Type 1 diabetes4000
Disease controls458163
  • *Reactivity with at least one of the three cN-1A peptides higher than cut-off.

  • †Disease controls: total of all disease control groups except IBM, SLE and SjS.

  • cN-1A, cytosolic 5′-nucleotidase 1A; IBM, inclusion body myositis; SjS, Sjögren's syndrome; SLE, systemic lupus erythematosus.