NeuroSURE® Metabolites: Sialic Acid, Cerebrospinal Fluid (CSF)
Use
CSF Sialic Acid is useful for diagnosing free sialic acid storage diseases. This testing may also be used for assessment of Variants of Uncertain Significance (VUS) identified during genetic testing (e.g. Next Generation Sequencing or Capillary Sequencing testing). Mutations in the SLC17A5 gene encoding the lysosomal transporter sialin are associated with the free sialic acid storage diseases (SASD): Salla disease (or the Finish type of sialuria), the more severe infantile free sialic acid storage disease (ISSD), and intermediate phenotypes with clinical findings of both Salla disease and ISSD. 1 SASD are characterized by the abnormal retention of free sialic acid in the lysosome (OMIM 604369 and 269920). Patients with SASD usually present with nystagmus, progressive cerebellar ataxia, spasticity, and severe psychomotor delay. Cerebellar ataxia may be the primary symptom. These symptoms are associated with diffuse supratentorial hypomyelination, thin corpus callosum, and cortical and cerebellar atrophy. In some patients, sialic acid increases are indentified only in CSF.
Special Instructions
Not provided.
Limitations
This test was developed and its performance characteristics determined by LabCorp, but it has not been cleared or approved by the FDA. It may not account for conditions outside the specified genetic mutations associated with SLC17A5. Therefore, the detection of sialic acid levels should be considered alongside clinical findings and not as a sole diagnostic tool.
Methodology
Mass Spectrometry
Biomarkers
Sialic Acid
Analyte
Result Turnaround Time
10-14 days
Related Documents
For more information, please review the documents below
Specimen
Cerebrospinal Fluid
Volume
1.0 mL
Minimum Volume
0.5 mL
Container
Sterile screw capped vial
Collection Instructions
Collect entire sample into a single sterile tube.
Storage Instructions
Freeze as soon as possible after collection.
Causes for Rejection
Bloody CSF; received thawed
Stability Requirements
| Temperature | Period |
|---|---|
| Room Temperature | Unstable |
| Refrigerated | 24 hours |
| Frozen | -20°C = 72 hours; -80°C = Indefinite |
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