Test Code ENS2M Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Serum
Additional Codes
MAYO: ENS2
EPIC: LAB1895
Ordering Guidance
Multiple neuroimmunology profile tests are available. For testing that is performed with each profile, see Autoimmune Neurology Antibody Matrix.
Necessary Information
Provide the following information:
-Relevant clinical information
-Ordering provider name, phone number, mailing address, and e-mail address
Specimen Required
Patient Preparation:
1. For optimal antibody detection, specimen collection is recommended prior to initiation of immunosuppressant medication or intravenous immunoglobulin treatment.
2. This test should not be requested in patients who have recently received radioisotopes, therapeutically or diagnostically, because of potential assay interference. The specific waiting period before specimen collection will depend on the isotope administered, the dose given, and the clearance rate in the individual patient. Specimens will be screened for radioactivity prior to analysis. Radioactive specimens received in the laboratory will be held 1 week and assayed if sufficiently decayed or canceled if radioactivity remains.
3. Patient should have no general anesthetic or muscle-relaxant drugs in the previous 24 hours.
Container Container/Tube:
Preferred: Red top
Acceptable: Serum gel
Submission Container/Tube: Plastic vial
Specimen Volume: 4 mL
Forms
If not ordering electronically, complete, print, and send Neurology Specialty Testing Client Test Request (T732) with the specimen.
Secondary ID
92116Useful For
Evaluating new onset encephalopathy (noninfectious or metabolic) comprising confusional states, psychosis, delirium, memory loss, hallucinations, movement disorders, sensory or motor complaints, seizures, dyssomnias, ataxias, nausea, vomiting, inappropriate antidiuresis, coma, dysautonomias, or hypoventilation in serum specimens
The following accompaniments should increase of suspicion for autoimmune encephalopathy:
-Headache
-Autoimmune stigmata (personal or family history or signs of diabetes mellitus, thyroid disorder, vitiligo, poliosis [premature graying], myasthenia gravis, rheumatoid arthritis, systemic lupus erythematosus)
-History of cancer
-Smoking history (over 20 pack-years) or other cancer risk factors
-Inflammatory cerebral spinal fluid (or isolated protein elevation)
-Neuroimaging signs suggesting inflammation
Evaluating limbic encephalitis (noninfectious)
Directing a focused search for cancer
Investigating encephalopathy appearing in the course or wake of cancer therapy and not explainable by metastasis or drug effect
Profile Information
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
AEESI | Encephalopathy, Interpretation, S | No | Yes |
AMPCS | AMPA-R Ab CBA, S | No | Yes |
AMPHS | Amphiphysin Ab, S | No | Yes |
AGN1S | Anti-Glial Nuclear Ab, Type 1 | No | Yes |
ANN1S | Anti-Neuronal Nuclear Ab, Type 1 | No | Yes |
ANN2S | Anti-Neuronal Nuclear Ab, Type 2 | No | Yes |
ANN3S | Anti-Neuronal Nuclear Ab, Type 3 | No | Yes |
CS2CS | CASPR2-IgG CBA, S | No | Yes |
CRMS | CRMP-5-IgG, S | No | Yes |
DPPIS | DPPX Ab IFA, S | No | Yes |
GABCS | GABA-B-R Ab CBA, S | No | Yes |
GD65S | GAD65 Ab Assay, S | Yes | Yes |
GFAIS | GFAP IFA, S | No | Yes |
IG5IS | IgLON5 IFA, S | No | Yes |
LG1CS | LGI1-IgG CBA, S | No | Yes |
GL1IS | mGluR1 Ab IFA, S | No | Yes |
NIFIS | NIF IFA, S | No | Yes |
NMDCS | NMDA-R Ab CBA, S | No | Yes |
PCABP | Purkinje Cell Cytoplasmic Ab Type 1 | No | Yes |
PCAB2 | Purkinje Cell Cytoplasmic Ab Type 2 | No | Yes |
PCATR | Purkinje Cell Cytoplasmic Ab Type Tr | No | Yes |
Reflex Tests
Test ID | Reporting Name | Available Separately | Always Performed |
---|---|---|---|
ARBI | ACh Receptor (Muscle) Binding Ab | Yes | No |
AGNBS | AGNA-1 Immunoblot, S | No | No |
AINCS | Alpha Internexin CBA, S | No | No |
AMPIS | AMPA-R Ab IF Titer Assay, S | No | No |
AMIBS | Amphiphysin Immunoblot, S | No | No |
AN1BS | ANNA-1 Immunoblot, S | No | No |
AN2BS | ANNA-2 Immunoblot, S | No | No |
CRMWS | CRMP-5-IgG Western Blot, S | Yes | No |
DPPCS | DPPX Ab CBA, S | No | No |
DPPTS | DPPX Ab IFA Titer, S | No | No |
GABIS | GABA-B-R Ab IF Titer Assay, S | No | No |
GFACS | GFAP CBA, S | No | No |
GFATS | GFAP IFA Titer, S | No | No |
IG5CS | IgLON5 CBA, S | No | No |
IG5TS | IgLON5 IFA Titer, S | No | No |
GL1CS | mGluR1 Ab CBA, S | No | No |
GL1TS | mGluR1 Ab IFA Titer, S | No | No |
NFHCS | NIF Heavy Chain CBA, S | No | No |
NIFTS | NIF IFA Titer, S | No | No |
NFLCS | NIF Light Chain CBA, S | No | No |
NMDIS | NMDA-R Ab IF Titer Assay, S | No | No |
PC1BS | PCA-1 Immunoblot, S | No | No |
PCTBS | PCA-Tr Immunoblot, S | No | No |
Testing Algorithm
If client requests or if immunofluorescence (IFA) patterns suggest collapsin response-mediator protein-5-IgG (CRMP-5-IgG), then CRMP-5-IgG Western blot, and ACh receptor (muscle) binding antibody are performed at an additional charge.
If IFA patterns suggest amphiphysin antibody, then amphiphysin immunoblot is performed at an additional charge.
If IFA pattern suggests antiglial nuclear antibody (AGNA)-1, then AGNA-1 immunoblot is performed at an additional charge.
If IFA pattern suggests antineuronal nuclear antibody (ANNA)-1, then ANNA-1 immunoblot is performed at an additional charge.
If IFA pattern suggests ANNA-2 antibody, then ANNA-2 immunoblot is performed at an additional charge.
If IFA pattern suggests Purkinje cytoplasmic antibody (PCA)-1, then PCA-1 immunoblot is performed at an additional charge.
If IFA pattern suggests PCA-Tr antibody, then PCA-Tr immunoblot is performed at an additional charge.
If IFA pattern suggests IgLON5 antibody, then IgLON5 IFA titer and IgLON5 cell-binding assay (CBA) is performed at an additional charge.
If IFA pattern suggests alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA)-receptor antibody, and AMPA-receptor antibody CBA is positive, then AMPA-receptor antibody IFA titer assay is performed at an additional charge.
If AMPA-receptor antibody CBA is positive, then CRMP-5-IgG Western blot, and acetylcholine (Ach) receptor (muscle) binding antibody are performed at an additional charge.
If contactin-associated protein-like-2 (CASPR2)-receptor antibody CBA is positive, then CRMP-5-IgG Western blot, and ACh receptor (muscle) binding antibody are performed at an additional charge.
If IFA pattern suggests gamma-aminobutyric acid B (GABA-B)-receptor antibody, and GABA-B-receptor antibody is positive, then GABA-B-receptor antibody IFA titer assay is performed at an additional charge.
If IFA pattern suggests glial fibrillary acidic protein (GFAP) antibody, then GFAP IFA titer and GFAP CBA are performed at an additional charge.
If IFA pattern suggests N-methyl-D-aspartate (NMDA)-receptor antibody, and NMDA-receptor antibody CBA is positive, then NMDA-receptor antibody IFA titer assay is performed at an additional charge.
If IFA pattern suggests dipeptidyl-peptidase-like protein-6 (DPPX) antibody, then DPPX antibody CBA and DPPX titer are performed at an additional charge.
If IFA pattern suggests metabotropic glutamate receptor 1 (mGluR1) antibody, then mGluR1 antibody CBA and mGluR1 titer are performed at an additional charge.
If IFA pattern suggests neuronal intermediate filament (NIF) antibody, then alpha internexin CBA, NIF heavy chain CBA, NIF light chain CBA, and NIF titer are performed at an additional charge.
For more information, see the following algorithms:
Autoimmune/Paraneoplastic Encephalopathy Evaluation Algorithm-Serum
Central Nervous System Demyelinating Disease Diagnostic Algorithm
Special Instructions
Method Name
AGN1S, AMPHS, AMPIS, ANN1S, ANN2S, ANN3S, CRMS, DPPIS, DPPTS, GABIS, GFAIS, GFATS, GL1IS, GL1TS, IG5IS, IG5TS, NIFIS, NIFTS, NMDIS, PCAB2, PCABP, PCATR: Indirect Immunofluorescence Assay (IFA)
AINCS, AMPCS, CS2CS, DPPCS, GABCS, GFACS, GL1CS, IG5CS, LG1CS, NFHCS, NFLCS, NMDCS: Cell-Binding Assay (CBA)
CRMWS: Western Blot (WB)
AGNBS, AMIBS, AN1BS, AN2BS, PC1BS, PCTBS: Immunoblot (IB)
ARBI, GD65S: Radioimmunoassay (RIA)
Reporting Name
Encephalopathy, Autoimm/Paraneo, SSpecimen Type
SerumSpecimen Minimum Volume
2.5 mL
Specimen Stability Information
Specimen Type | Temperature | Time | Special Container |
---|---|---|---|
Serum | Refrigerated (preferred) | 28 days | |
Frozen | 28 days | ||
Ambient | 72 hours |
Reject Due To
Gross hemolysis | Reject |
Gross lipemia | Reject |
Gross icterus | Reject |
Reference Values
Test ID |
Reporting name |
Methodology* |
Reference value |
AEESI |
Encephalopathy, Interpretation, S |
Medical interpretation |
NA |
AMPCS |
AMPA-R Ab CBA, S |
CBA |
Negative |
AMPHS |
Amphiphysin Ab, S |
IFA |
<1:240 |
AGN1S |
Anti-Glial Nuclear Ab, Type 1 |
IFA |
<1:240 |
ANN1S |
Anti-Neuronal Nuclear Ab, Type 1 |
IFA |
<1:240 |
ANN2S |
Anti-Neuronal Nuclear Ab, Type 2 |
IFA |
<1:240 |
ANN3S |
Anti-Neuronal Nuclear Ab, Type 3 |
IFA |
<1:240 |
CS2CS |
CASPR2-IgG CBA, S |
CBA |
Negative |
CRMS |
CRMP-5-IgG, S |
IFA |
<1:240 |
DPPIS |
DPPX Ab IFA, S |
IFA |
Negative |
GABCS |
GABA-B-R Ab CBA, S |
CBA |
Negative |
GD65S |
GAD65 Ab Assay, S |
RIA |
≤0.02 nmol/L Reference values apply to all ages. |
GFAIS |
GFAP IFA, S |
IFA |
Negative |
IG5IS |
IgLON5 IFA, S |
IFA |
Negative |
LG1CS |
LGI1-IgG CBA, S |
CBA |
Negative |
GL1IS |
mGluR1 Ab IFA, S |
IFA |
Negative |
NIFIS |
NIF IFA, S |
IFA |
Negative |
NMDCS |
NMDA-R Ab CBA, S |
CBA |
Negative |
PCABP |
Purkinje Cell Cytoplasmic Ab Type 1 |
IFA |
<1:240 |
PCAB2 |
Purkinje Cell Cytoplasmic Ab Type 2 |
IFA |
<1:240 |
PCATR |
Purkinje Cell Cytoplasmic Ab Type Tr |
IFA |
<1:240 |
Reflex Information:
Test ID |
Reporting name |
Methodology* |
Reference value |
ARBI |
ACh Receptor (Muscle) Binding Ab |
RIA |
≤0.02 nmol/L |
AGNBS |
AGNA-1 Immunoblot, S |
IB |
Negative |
AINCS |
Alpha Internexin CBA, S |
CBA |
Negative |
AMPIS |
AMPA-R Ab IF Titer Assay, S |
IFA |
<1:120 |
AMIBS |
Amphiphysin Immunoblot, S |
IB |
Negative |
AN1BS |
ANNA-1 Immunoblot, S |
IB |
Negative |
AN2BS |
ANNA-2 Immunoblot, S |
IB |
Negative |
CRMWS |
CRMP-5-IgG Western Blot, S |
WB |
Negative |
DPPCS |
DPPX Ab CBA, S |
CBA |
Negative |
DPPTS |
DPPX Ab IFA Titer, S |
IFA |
<1:240 |
GABIS |
GABA-B-R Ab IF Titer Assay, S |
IFA |
<1:120 |
GFACS |
GFAP CBA, S |
CBA |
Negative |
GFATS |
GFAP IFA Titer, S |
IFA |
<1:240 |
IG5CS |
IgLON5 CBA, S |
CBA |
Negative |
IG5TS |
IgLON5 IFA Titer, S |
IFA |
<1:240 |
GL1CS |
mGluR1 Ab CBA, S |
CBA |
Negative |
GL1TS |
mGluR1 Ab IFA Titer, S |
IFA |
<1:240 |
NFHCS |
NIF Heavy Chain CBA, S |
CBA |
Negative |
NIFTS |
NIF IFA Titer, S |
IFA |
<1:240 |
NFLCS |
NIF Light Chain CBA, S |
CBA |
Negative |
NMDIS |
NMDA-R Ab IF Titer Assay, S |
IFA |
<1:120 |
PC1BS |
PCA-1 Immunoblot, S |
IB |
Negative |
PCTBS |
PCA-Tr Immunoblot, S |
IB |
Negative |
*Methodology abbreviations:
Immunofluorescence assay (IFA)
Cell-binding assay (CBA)
Western blot (WB)
Radioimmunoassay (RIA)
Immunoblot (IB)
Neuron-restricted patterns of IgG staining that do not fulfill criteria for ANNA-1, ANNA-2, 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."
Note: CRMP-5 titers lower than 1:240 are detectable by recombinant CRMP-5 Western blot analysis. CRMP-5 Western blot analysis will be done on request on stored serum (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.
Day(s) Performed
Profile tests: Monday through Sunday; Reflex tests: Varies
Report Available
10 to 13 daysPerforming Laboratory

Test Classification
This test was developed, and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. This test has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
86255 x 19
86341 x 1
83519-ARBI (if appropriate)
84182-AGNBS (if appropriate)
86255-AINCS (if appropriate)
86256-AMPIS (if appropriate)
84182-AMIBS (if appropriate)
84182-AN1BS (if appropriate)
84182-AN2BS (if appropriate)
84182-CRMWS (if appropriate)
86255-DPPCS (if appropriate)
86256-DPPTS (if appropriate)
86256-GABIS (if appropriate)
86255-GFACS (if appropriate)
86256-GFATS (if appropriate)
86255-IG5CS (if appropriate)
86256-IG5TS (if appropriate)
86255-GL1CS (if appropriate)
86256-GL1TS (if appropriate)
86255-NFHCS (if appropriate)
86256-NIFTS (if appropriate)
86255-NFLCS (if appropriate)
86256-NMDIS (if appropriate)
84182-PC1BS (if appropriate)
84182-PCTBS (if appropriate)
LOINC Code Information
Test ID | Test Order Name | Order LOINC Value |
---|---|---|
ENS2 | Encephalopathy, Autoimm/Paraneo, S | 94697-0 |
Result ID | Test Result Name | Result LOINC Value |
---|---|---|
61516 | NMDA-R Ab CBA, S | 93503-1 |
61518 | AMPA-R Ab CBA, S | 93489-3 |
61519 | GABA-B-R Ab CBA, S | 93428-1 |
34257 | Encephalopathy, Interpretation, S | 69048-7 |
64279 | LGI1-IgG CBA, S | 94287-0 |
64281 | CASPR2-IgG CBA, S | 94285-4 |
64930 | DPPX Ab IFA, S | 82976-2 |
64928 | mGluR1 Ab IFA, S | 94347-2 |
605155 | GFAP IFA, S | 94346-4 |
606946 | IgLON5 IFA, S | 96476-7 |
606964 | NIF IFA, S | 96486-6 |
89080 | AGNA-1, S | 94341-5 |
81722 | Amphiphysin Ab, S | 94340-7 |
80150 | ANNA-1, S | 94342-3 |
80776 | ANNA-2, S | 94343-1 |
83137 | ANNA-3, S | 94344-9 |
83077 | CRMP-5-IgG, S | 94815-8 |
81596 | GAD65 Ab Assay, S | 94345-6 |
83138 | PCA-2, S | 94351-4 |
9477 | PCA-1, S | 94350-6 |
83076 | PCA-Tr, S | 94352-2 |
36349 | Reflex Added | 77202-0 |