Collapsin Response-Mediator Protein-5-IgG, Western Blot, Spinal Fluid

Casandra

Casandra Test Code MC78636Version 1 (DRAFT)

Performing Lab

Lab Mayo Clinic LabLab Test ID CRMWCCPT Code 84182

Collapsin Response-Mediator Protein-5-IgG, Western Blot, Spinal Fluid

Clinical Use

Use

The CRMP-5-IgG test is useful for evaluating cases of subacute chorea, vision loss, cranial neuropathy, and myelopathy. It detects autoantibodies specific for neurons and muscle, which are significant serological markers of neurological autoimmunity. These autoantibodies are often predictive of neoplasms such as small-cell lung carcinomas (SCLC) and thymoma. CRMP-5-IgG is a more common autoantibody accompaniment of SCLC than antineuronal nuclear antibodies-1 (ANNA-1; anti-Hu) and may occur with thymoma. The test is indicated particularly when interfering autoantibodies preclude identification by standard immunofluorescence.

Special Instructions

It is recommended to order phenotype-specific autoimmune/paraneoplastic evaluations in conjunction with this test if not previously performed. Multiple neurological phenotype-specific evaluations are available, and for more information, the Autoimmune Neurology Test Ordering Guide should be consulted.

Limitations

CRMP-5-IgG may not be detectable by standard immunofluorescence if the titer is low or if coexisting autoantibodies obscure detection. The test uses a Western blot analysis, which is effective when standard assays are ambiguous or negative in the presence of suggestive neurological symptoms.

Test Details

New York Approved