Autoimmune Encephalitis Panel, CSF (Sendout)
General Information
- Lab Name
- Autoimmune Encephalitis Panel, CSF (Sendout)
- Lab Code
- RCAENP
- Epic Name
- Autoimmune Encephalitis Panel, CSF (Sendout)
- External Test Id
- ENC2
- Description
Test Information: Encephalitis is a debilitating neurologic condition caused by infectious and autoimmune conditions that result in inflammation of the brain parenchyma. The identification of autoantibodies may augment a diagnosis of autoimmune encephalitis, but is not required for the diagnosis or initiation of therapy. The most frequently identified antibodies target NMDA-R. We recommend ordering NMDA Receptor IgG Antibody with Reflex, CSF (Sendout) [RCNMDA] as first-line testing for autoimmune encephalitis prior to ordering this full panel.
Monitoring titers over time for these antibodies is not recommended; however, this recommendation is based on limited currently available literature.
Test Algorithm: Reflex testing may be performed at additional charge. Refer to Mayo's algorithm (linked below) for additional detail on tests and potential reflex tests included in this panel.
Ordering Guidance: Refer to Autoimmune Encephalitis Testing Recommendations or consult the Laboratory Medicine Resident on-call.
- The Mayo Antibody Prevalence in Epilepsy and Encephalopathy (APE²) Scorecard may be used to determine the likelihood of neural antibody positivity in patients with encephalopathy and/or seizures.
- References
- Mayo Clinical & Interpretive Information: Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
- Synonyms
- AGNA-1, AMPA-R Antibody CBA, Amphiphysin Antibody, ANNA-1, ANNA-2, ANNA-3, Anti-Glial Nuclear Antibody, Anti-Neuronal Nuclear Antibody Type 1, Anti-Neuronal Nuclear Antibody Type 2, Anti-Neuronal Nuclear Antibody Type 3, CASPR2 IgG CBA, Contactin-Associated Protein-Like-2 (CASPR2) IgG, CRMP-5 IgG, Dipeptidyl-Peptidase-Like Protein-6 (DPPX) Antibody, DPPX Ab CBA, ENC1, ENC2, Encephalopathy, Encephalopathy Autoimmune Paraneoplastic Evaluation, Encephalopathy Autoimmune/Paraneoplastic Evaluation Spinal Fluid, GABA-B-R Antibody CBA, GAD65 Antibody Assay, GFAP IFA, Glutamic Acid Decarboxylase, IgLON Family Member 5 Antibody, IgLON5 Ab CBA, Leucine-Rich Glioma Inactivated Protein-1 IgG, LGI1 IgG CBA, mGluR1 Ab IFA, Neurochondrin IFA, NIF IFA, NMDA-R Antibody CBA, PCA-1, PCA-2, PCA-Tr, PDE10A IFA, Purkinje Cell Cytoplasmic Antibody Type 1, Purkinje Cell Cytoplasmic Antibody Type 2, Purkinje Cell Cytoplasmic Antibody Type Tr, Septin-7 IFA, TRIM46 IFA
- Components
-
Code Name RCENCI Encephalopathy, Interpretation, CSF RIFANT IFA Notes RCAMPA AMPA Receptor Ab CBA, CSF RCAMPH Amphiphysin Ab, CSF RCAGN1 Anti Glial Nuclear Ab, Type 1, CSF RCANA1 Anti Neuronal Nuclear Ab Type 1, CSF RCANN2 Anti Neuronal Nuclear Ab Type 2, CSF RCANN3 Anti Neuronal Nuclear Ab Type 3, CSF RCSPR2 CASPR2 IgG CBA, CSF RCRMP5 CRMP 5 IgG, CSF RCDPPC DPPX Antibody CBA, CSF RCGABA GABA B Receptor Ab CBA, CSF RCGD65 GAD65 Ab Assay, CSF RCGFAP GFAP IFA, CSF RCMGR1 mGluR1 Ab IFA, CSF RCIG5C IgLON5 CBA, CSF RCLGI1 LGI1 IgG CBA, CSF RNCDIC Neurochondrin IFA, CSF RNIFIC NIF IFA, CSF RCNMDC NMDA Receptor Ab CBA, CSF RCPCAT Purkinje Cell Cytoplasmc Ab Type Tr, CSF RCPCY1 Purkinje Cell Cytoplasmic Ab Type 1, CSF RCPCA2 Purkinje Cell Cytoplasmic Ab Type 2, CSF RCPDE1 PDE10A Antibody IFA, CSF RSP7IC Septin 7 IFA, CSF RCTR46 TRIM46 Antibody IFA, CSF
Interpretation
- Guidelines
- Method
Indirect Immunofluorescence Assay (IFA): ANNA-1, ANNA-2, ANNA-3, AGNA-1, PCA-1, PCA-2, PCA-Tr, Amphiphysin Ab, CRMP-5 IgG, GFAP, mGluR1 Ab, Neurochondrin Ab, Septin-7 Antibody, PDE10A Ab, TRIM46 Ab
Cell-Binding Assay (CBA): AMPA-R Ab, GABA-B-R Ab, NMDA-R Ab CBA, LGI1-IgG CBA, CASPR2-IgG, DPPX Ab, IgLON5 Ab
Radioimmunoassay (RIA): GAD65 Ab
- Reference Range
- See individual components
- Ref. Range Notes
Reference Values:
AMPA-R Ab CBA, CSF: Negative Amphiphysin Ab, CSF: Negative Anti-Glial Nuclear Ab, Type 1, CSF: Negative Anti-Neuronal Nuclear Ab, Type 1, CSF: Negative Anti-Neuronal Nuclear Ab, Type 2, CSF: Negative Anti-Neuronal Nuclear Ab, Type 3, CSF: Negative CASPR2-IgG CBA, CSF: Negative CRMP-5-IgG, CSF: Negative DPPX Ab CBA, CSF: Negative GABA-B-R Ab CBA, CSF: Negative GAD65 Ab Assay, CSF: < or =0.02 nmol/L GFAP IFA, CSF: Negative mGluR1 Ab IFA, CSF: Negative IgLON5 CBA, CSF: Negative LGI1-IgG CBA, CSF: Negative Neurochondrin IFA, CSF: Negative NIF IFA, CSF: Negative NMDA-R Ab CBA, CSF: Negative Purkinje Cell Cytoplasmc Ab Type Tr: Negative Purkinje Cell Cytoplasmic Ab Type 1: Negative Purkinje Cell Cytoplasmic Ab Type 2: Negative PDE10A Ab IFA, CSF: Negative Septin-7 IFA, CSF: Negative TRIM46 IFA, CSF: Negative Note: Includes reference values for panel tests only.
Neuron-restricted patterns of IgG staining that do not fulfill criteria for ANNA-1, ANNA-2, ANNA-3, CRMP-5-IgG, PCA-1, PCA-2, or PCA-Tr may be reported as "unclassified anti-neuronal IgG." Complex patterns that include nonneuronal elements may be reported as "uninterpretable."
CRMP-5 titers lower than 1:2 are detectable by recombinant CRMP-5 Western blot analysis. CRMP-5 Western blot analysis will be done on request on stored spinal fluid (held 4 weeks). This supplemental testing is recommended in cases of chorea, vision loss, cranial neuropathy, and myelopathy. Call the Neuroimmunology Laboratory at 800-533-1710 to request CRMP-5 Western blot.
Interpretation:
Neuronal, glial, and muscle autoantibodies are valuable serological markers of autoimmune encephalopathy and of a patient's immune response to cancer. These autoantibodies are usually accompanied by subacute neurological symptoms and signs are not found in healthy subjects. It is not uncommon for more than 1 of the following autoantibody specificities to be detected in patients with an autoimmune encephalopathy:
- Plasma membrane autoantibodies: These are all potential effectors of neurological dysfunction: N-methyl-D-aspartate (NMDA) receptor; 2-amino-3-(5-methyl-3-oxo-1,2- oxazol-4-yl) propanoic acid (AMPA) receptor; gamma-amino butyric acid (GABA-B) receptor; neuronal acetylcholine receptor.
- Neuronal nuclear autoantibodies: type 1 (ANNA-1), type 2 (ANNA-2), or type 3 (ANNA-3)
- Neuronal or muscle cytoplasmic antibodies: amphiphysin, Purkinje cell antibodies (PCA-1 and PCA-2), collapsin response-mediator protein-5 (CRMP-5), or glutamic acid decarboxylase (GAD65).
- Interferences and Limitations
This test is intended to be ordered for adult patients. If this test is ordered for a patient younger than 18 years of age, it will be canceled and automatically reordered by the laboratory as PCDEC/ Pediatric Autoimmune Encephalopathy/CNS Disorder Evaluation, Spinal Fluid. The pediatric autoimmune CNS disorders evaluation is part of an evolving approach to testing for autoimmune neurological disorders using phenotypic-specific evaluations that include multiple antibodies known for their disease association.
- References
- Mayo Clinical & Interpretive Information: Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Spinal Fluid
Ordering & Collection
- Specimen Type
- CSF
- Collection
-
Collect 4 mL CSF and transfer to a sterile vial.
- Approval Required
- LMR approval is not required.
- Handling Instructions
Outside Laboratories: Refrigerate CSF in a sterile vial.
Stability: Refrigerated (preferred): 28 days; Frozen: 28 days; Ambient: 72 hours.
- Quantity
-
Requested: 4 mL CSF
Minimum: 2 mL CSF
Processing
- Receiving Instructions
SPS: Use container code CSF4 to route this order in Sunquest SMART.
Refrigerate CSF in a sterile vial.
- Note: Sterile vial is preferred, but CSF samples transferred to a polypropylene aliquot will still be accepted by Mayo.
Sendouts:
- Order Mayo Test: ENC2.
- Interfaced: Yes.
Stability: Refrigerated (preferred): 28 days; Frozen: 28 days; Ambient: 72 hours.
- Misc Sendout
Performance
- Lab Department
- Sendouts Mayo Lab (RF)(MARF)
- Frequency
- Performed: Monday - Sunday. Report Available: 5-10 days from sample receipt at Mayo Clinic Labs. Allow additional time for reflex testing, if performed.
- Available STAT?
- No
- Performing Location(s)
-
Sendout Mayo Clinic Laboratories
800-533-1710200 First Street Southwest
Rochester, MN 55901
Billing & Coding
- CPT Codes
- 86255x23, 86341
- LOINC
- 94708-5
- Interfaced Order Code
- UOW4080
- Billing Comments
Reflex testing may be performed at additional charge.