Alternative name: Purkinje cell antibodies, Neuronal antibodies
Description: A family of autoantibodies recognising antigens in the brain which are associated with a variety of neurological manifestations occurring as a result of malignancy, usually ovarian or small cell carcinoma of the lung. The autantibodies may also recognise the tumour. Patients present with paraneoplastic cerebellar degeneration usually triggering a search for a previously unsuspected malignancy.There are several groups of autantibodies:

  • Anti-neuronal nuclear autoantibodies (ANNA) recognise neuronal nucleii (not including nucleoli) but not nucleii from other tissues.
  • ANNA1 (Hu) are reactive with all neuronal nucleii especially purkinje cells but not glial cells.
  • ANNA 2 (Ri) do not recognise nucleii of the peripheral nervous system.
  • Purkinje cell cytoplasmic antibodies (PCCA or Yo antibodies recognise cerebellar tissue as a course granular staining of the Purkinje cell (no nuclear staining).
  • Positive samples are confirmed by immunoblotting which detects anti-Hu,Yo and Ri but also MA1,MA2, CV2/CRMP5 and amphiphysin antibodies.

See also anti-GAD antibodies and antibodies to voltage gated calcium or potassium channels.

This is a rapidly expanding field with new autoantibodies recognised annually. However, the diagnostic significance of many of the hew autoantibodies is poorly defined.

Indication: Paraneoplastic cerebellar syndrome & neuropathies associated with ovarian and small cell carcinoma of the lung.
Interpretation: Hu antibodies associated with several neurological syndromes including subacute sensory neuropathy and encephelomyelits usually patients with small cell carcinoma. Ri antibodies associated with opsoclonus, ataxia, mystagmus and/or dysarthia usually patients with breast cancer. Yo antibodies associated with cerebellar symptoms; usually patients with ovarian cancer. An increasing number of paraneoplastic antibodies are being characterised.
Sample: Serum Separator Tube (SST)
Assay details: Indirect immunfluorescence rabbit cerebellum and other tissues
Restrictions: Referred test: only available to Neurology staff.
Reference range: Positive or negative
Assay range notes:
Turnaround time: 28 days
Analysing laboratory: Churchill Hospital Department of Immunology