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ENA antibodies – includes Ro (SS-A52, SS-A60), La (SS-B), Sm/RNP, RNP (RNPA, RNP68), Sm, Jo-1, Scl-70, Ribosomal P and Chromatin

General information

Antibodies to extractable nuclear antigens are of use in the classification of clinical subsets of connective tissue diseases and in providing prognostic information.

Specimen transport: At room temperature

Repeat frequency: Not more than once a year, unless clinical picture has changed

Special precautions: None

Laboratory information

Normal reference range: <0-0.9 AI

Volume and sample type: 7ml clotted blood

Method: Multiplex flow immunoassay

Turnaround time (calendar days from sample receipt to authorised result): Median - 1

Clinical information

Indications for the test:

  • Anti-Ro (SS-A) - SLE, Sjögren's syndrome, neonatal lupus. In pregnancy it may cause congenital defects
  • Anti-La (SS-B) - SLE, Sjögren's syndrome, neonatal lupus
  • Anti-Sm - SLE
  • Anti-RNP - SLE, Mixed connective tissue disease
  • Anti-Scl 70 - Progressive systemic sclerosis (generalised scleroderma)
  • Anti-Jo-1 - Polymyositis, Dermatomyositis
  • Anti-Ribo P - Neuro-SLE
  • Anti-Chromatin - SLE nephritis

Factors affecting the test: None


ICE reference: ENA Antibodies


(Last updated August 22nd 2018)