title: Anti-signal recognition particle antibody in patients without inflammatory myopathy: a survey of 6180 patients with connective tissue diseases.
abstract: OBJECTIVE
  To clarify the prevalence of anti-signal recognition particle (anti-SRP) antibody in connective tissue diseases (CTDs) and investigate the clinical characteristics of patients without inflammatory myopathy.
  
  
  METHODS
  Sera from 6180 patients with CTD were examined by immunoprecipitation (IPP) assays, and the records of patients positive for anti-SRP antibody were reviewed retrospectively. The antibody against the 54-kDa protein of SRP (SRP54) was quantified by enzyme-linked immunosorbent assay (ELISA) in patients with anti-SRP antibody.
  
  
  RESULTS
  Of the 28 patients positive for anti-SRP antibody, nine (32.1%) did not have inflammatory myopathy. The clinical diagnoses and characteristics of those patients varied considerably. In patients with inflammatory myopathy, the index of anti-SRP54 was much higher than in those without myopathy (1.15 vs. 0.46; p = 0.036).
  
  
  CONCLUSIONS
  The prevalence of anti-SRP antibody was 0.5% in a cohort of Japanese patients with CTD, and one-third of them did not have inflammatory myopathy. Sera from patients with inflammatory myopathy recognized SRP54 more strongly than in those without myopathy.
authors: a Division of Rheumatology, Department of Internal Medicine , Keio University School of Medicine , Tokyo , Japan.
authors: H
authors: H
authors: Hanaoka
authors: a Division of Rheumatology, Department of Internal Medicine , Keio University School of Medicine , Tokyo , Japan.
authors: Y
authors: Y
authors: Kaneko
authors: b Department of Neurology , Keio University School of Medicine , Tokyo , Japan.
authors: S
authors: S
authors: Suzuki
authors: a Division of Rheumatology, Department of Internal Medicine , Keio University School of Medicine , Tokyo , Japan.
authors: T
authors: T
authors: Takada
authors: a Division of Rheumatology, Department of Internal Medicine , Keio University School of Medicine , Tokyo , Japan.
authors: M
authors: M
authors: Hirakata
authors: a Division of Rheumatology, Department of Internal Medicine , Keio University School of Medicine , Tokyo , Japan.
authors: T
authors: T
authors: Takeuchi
authors: a Division of Rheumatology, Department of Internal Medicine , Keio University School of Medicine , Tokyo , Japan.|c Department of Allergy and Rheumatology , Nippon Medical School Graduate School of Medicine , Tokyo , Japan.
authors: M
authors: M
authors: Kuwana