Turnaround times
The quoted turnaround time is from sample receipt in the laboratory, to results authorisation in the Laboratory Information Management system. The times do not include transport of specimen to the laboratory or the administrative process to print and post/email reports. Service users must allow for transport and reporting time when ordering tests.
Clinical background:
Analysis of amino acids in CSF is performed for the investigation of a metabolic cause of intractable seizures or other severe neurological disease. The profile includes glycine (required for diagnosis of non-ketotic hyperglycinaemia) and serine (for diagnosis of serine synthesis disorders). A paired plasma sample should be taken for comparison of CSF amino acid results with those in plasma.
Specimen container paediatric:
CSF in universal tube
Specimen container adult:
CSF in universal tube
Minimum volume paediatric:
0.5 mL CSF
Minimum volume adult:
0.5 mL CSF
Special requirements:
Send with a paired plasma sample
Sample stability:
4 hours at ambient temperatureFrozen 6 months
Transport requirements:
Ward: Send to laboratory at ambient temperature
External laboratories: send frozen to RVI
Availability:
Available during full access hours
Assayed twice weekly
Site of analysis: RVI
Quality assurance:
ERNDIM
Interpretation:
Ratios of CSF:plasma amino acids are reported where appropriate.Contamination of the CSF sample with traces of blood will cause falsely elevated concentrations of amino acids.Some drugs (e.g. valproate) can cause increased CSF amino acids.Results will be interpreted in context of the clinical information and results of other laboratory investigations. It is therefore essential that clinical details are supplied with requests, including current medication.
Reference ranges:
Age-related reference ranges and interpretation provided on laboratory report