Test Code AK5CS Adenylate Kinase 5 (AK5) IgG, Cell Based Assay, Serum (Non-Orderable)
Specimen Required
Only orderable as a reflex. For more information see:
-DMS2 / Dementia, Autoimmune/Paraneoplastic Evaluation, Serum
-ENS2 / Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Serum
-EPS2 / Epilepsy, Autoimmune/Paraneoplastic Evaluation, Serum
Secondary ID
623401Useful For
Only orderable as a reflex. For more information see:
DMS2 / Dementia, Autoimmune/Paraneoplastic Evaluation, Serum
ENS2 / Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Serum
EPS2 / Epilepsy, Autoimmune/Paraneoplastic Evaluation, Serum
Evaluation of patients suspected of having autoimmune encephalitis using serum specimens
Reporting adenylate kinase 5 IgG results as part of a profile
Method Name
Only orderable as a reflex. For more information see:
-DMS2 / Dementia, Autoimmune/Paraneoplastic Evaluation, Serum
-ENS2 / Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Serum
-EPS2 / Epilepsy, Autoimmune/Paraneoplastic Evaluation, Serum
Cell Binding Assay (CBA)
Reporting Name
AK5 Ab CBA, SSpecimen Type
SerumSpecimen Minimum Volume
Serum: 0.5 mL
Specimen Stability Information
| Specimen Type | Temperature | Time |
|---|---|---|
| Serum | Refrigerated (preferred) | 28 days |
| Frozen | 28 days | |
| Ambient | 72 hours |
Reject Due To
| Gross hemolysis | Reject |
| Gross lipemia | Reject |
| Gross icterus | Reject |
Clinical Information
Adenylate kinase 5 IgG (AK5-IgG) is a marker intended for evaluating patients with autoimmune encephalitis, most often presenting as a non-paraneoplastic limbic encephalitis. Poor response to immunotherapy has been reported while there is no clear cancer association (non-paraneoplastic). AK5-IgG positive patients present with predominant severe amnestic syndrome, associated depression, and anxiety. Epilepsy is often absent at disease onset, however seizures may develop later.
Reference Values
Only orderable as a reflex. For more information see:
-DMS2 / Dementia, Autoimmune/Paraneoplastic Evaluation, Serum
-ENS2 / Encephalopathy, Autoimmune/Paraneoplastic Evaluation, Serum
-EPS2 / Epilepsy, Autoimmune/Paraneoplastic Evaluation, Serum
Negative
Interpretation
A positive result is consistent with adenylate kinase 5 autoimmunity that manifests with non-paraneoplastic limbic encephalitis.
Method Description
Patient specimen is applied to a composite slide containing transfected and non-transfected human embryonic kidney (HEK293) cells. After incubation and washing, fluorescein-conjugated goat-antihuman IgG is applied to detect the presence of patient IgG binding.(Unpublished Mayo method)
Day(s) Performed
Varies
Performing Laboratory
Mayo Clinic Laboratories in Rochester
Test Classification
This test was developed and its performance characteristics determined by Mayo Clinic in a manner consistent with CLIA requirements. It has not been cleared or approved by the US Food and Drug Administration.CPT Code Information
86255
LOINC Code Information
| Test ID | Test Order Name | Order LOINC Value |
|---|---|---|
| AK5CS | AK5 Ab CBA, S | In Process |
| Result ID | Test Result Name | Result LOINC Value |
|---|---|---|
| 623401 | AK5 Ab CBA, S | In Process |