Ordering Recommendation

Molecular (DNA) test to confirm a diagnosis of primary carnitine deficiency following clinical and/or biochemical presentation. To diagnose or rule out primary carnitine deficiency, refer to Carnitine, Free & Total (Includes Carnitine, Esterified) (0080068).

Mnemonic
PCD FGS
Methodology

Polymerase Chain Reaction/Sequencing

Performed

Varies

Reported

14-21 days

New York DOH Approval Status
Specimens from New York clients will be sent out to a New York DOH approved laboratory, if possible.
Specimen Required
Patient Preparation
Collect

Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).

Specimen Preparation

Transport 3 mL whole blood. (Min: 1 mL)

Storage/Transport Temperature

Refrigerated.

Unacceptable Conditions
Remarks
Stability

Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable

Reference Interval
Interpretive Data

Background information for Primary Carnitine Deficiency (SLC22A5) Sequencing:
Characteristics: Hypoketotic hypoglycemia during periods of fasting, hepatomegaly, Reye syndrome, sudden infant death, developmental delay, cardiac and/or skeletal myopathy, hypotonia and enlarged heart.
Incidence: 1 in 40,000 for European Caucasian and Japanese, lower in other populations.
Inheritance: Autosomal recessive.
Cause: Deleterious SLC22A5 gene mutations causing a non-functional protein (OCTN2).
Clinical Sensitivity: Approximately 82 percent.
Methodology: Bidirectional sequencing of the entire coding region and intron/exon boundaries of SLC22A5 gene.
Analytical Sensitivity: Greater than 99 percent.
Limitations: Mutations in genes other than SLC22A5 will not be detected; large deletions, deep intronic mutations and promoter mutations in the SLC22A5 gene are not detected by this assay; analytical sensitivity may be compromised by rare primer site mutations. Diagnostic errors can occur due to rare sequence variations.

Compliance Category

Laboratory Developed Test (LDT)

Note
Hotline History
N/A
CPT Codes

81405

Components
Component Test Code* Component Chart Name LOINC
0051681 PCD Sequencing Interpretation
2001371 PCD FGS Specimen
* Component test codes cannot be used to order tests. The information provided here is not sufficient for interface builds; for a complete test mix, please click the sidebar link to access the Interface Map.
Aliases
  • OCTN2 Sequencing
  • SLC22A5 sequencing
Primary Carnitine Deficiency (SLC22A5) Sequencing