Myopathy associated with antibodies to signal recognition particle: disease progression and neurological outcome

Arch Neurol. 2012 Jun;69(6):728-32. doi: 10.1001/archneurol.2011.1728.


Objective: To characterize the clinical course of myopathy associated with antibodies to signal recognition particle (SRP), or anti-SRP myopathy.

Design: Case series.

Setting: Keio University Hospitals and National Institute of Neuroscience, National Center of Neurology and Psychiatry, Tokyo, Japan.

Patients: We reviewed clinical features of 27 patients with anti-SRP myopathy and analyzed disease progression and neurological outcome.

Main outcome measures: Anti-SRP antibodies in serum were detected by RNA immunoprecipitation assay using extracts of K562 cells.

Results: Of the 27 patients, 5 (19%) showed chronic progressive muscle weakness as well as atrophy of limbs and trunk muscles from a younger age with more severe neurological outcomes compared with the other 22 patients(81%) with the subacute form.

Conclusion: A subset of patients with anti-SRP myopathy can show a chronic progressive form associated with severe clinical deficits.

Publication types

  • Multicenter Study

MeSH terms

  • Adolescent
  • Adult
  • Age of Onset
  • Aged
  • Aged, 80 and over
  • Anti-Inflammatory Agents / therapeutic use
  • Autoantibodies / blood*
  • Creatine Kinase / blood
  • Disease Progression
  • Female
  • Humans
  • Immunoprecipitation
  • Male
  • Middle Aged
  • Muscular Diseases / blood*
  • Muscular Diseases / complications
  • Muscular Diseases / drug therapy
  • Muscular Diseases / immunology*
  • Nervous System Diseases / etiology*
  • Prednisolone / therapeutic use
  • Severity of Illness Index
  • Signal Recognition Particle / immunology*
  • Young Adult


  • Anti-Inflammatory Agents
  • Autoantibodies
  • Signal Recognition Particle
  • Prednisolone
  • Creatine Kinase