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 acylcarnitines is performed in the investigation of fatty acid oxidation disorders and some organic acid disorders. For the majority of cases, bloodspot acylcarnitines is the preferred test.
Plasma acylcarnitines analysis is recommended when disorders of metabolism of long-chain species are suspected e.g. carnitine palmitoyltransferase II (CPT2) or carnitine translocase (carnitine acylcarnitine carrier) deficiencies. The test is not recommended for investigation of carnitine palmitoyltransferase I (CPT1) deficiency; blood spot acylcarnitine analysis is a more sensitive assay for this disorder.
The clinical presentation of the patient and results of other laboratory investigations are used to help with interpretation of results of acylcarnitine profiles. It is therefore very important to provide relevant clinical information with requests.
Note that the turnaround time for plasma acylcarnitines is longer than for blood spot acylcarnitines analysis.
Specimen container paediatric:
EDTA plasma
Specimen container adult:
EDTA plasma
Minimum volume paediatric:
0.5 mL
Minimum volume adult:
0.5 mL
Sample stability:
Plasma acylcarnitines are stable at ambient temperature for 48 hours and at -20°C for 3 months.
Transport requirements:
NUTH users: send blood sample to the laboratory at ambient temperature
External hospitals: separate plasma and send at ambient temperature by first class post. If there is a delay in transport of the sample, store at -20°C before posting.
Quality assurance:
CDC, NEQAS, ERNDIM
Interpretation:
Each result is issued with an interpretation and advice as to follow up investigations if appropriate.
Reference ranges:
Reported with interpretative comment.
Other info:
Lithium-heparin plasma and serum samples are acceptable. State sample type on form.