Use to confirm a diagnosis of citrullinemia type II (or citrin deficiency) following clinical and/or biochemical findings.
- Patient Preparation
- Lavender (EDTA), pink (K2EDTA), or yellow (ACD Solution A or B).
- Specimen Preparation
- Transport 3 mL whole blood. (Min: 1 mL)
- Storage/Transport Temperature
- Unacceptable Conditions
- Ambient: 72 hours; Refrigerated: 1 week; Frozen: Unacceptable
Characteristics: Citrin deficiency is a urea cycle disorder resulting in two distinct phenotypes: citrullinemia type II (CTLN2) and neonatal intrahepatic cholestasis caused by citrin deficiency (NICCD). CTLN2 is characterized by adult onset recurrent episodes of hyperammonemia and associated neuropsychiatric symptoms. NICCD is characterized by transient intrahepatic cholestasis in infancy.
Incidence: Varies by population. Approximately 1 in 19,000 in individuals of Japanese ethnicity.
Inheritance: Autosomal recessive.
Cause: Pathogenic SLC25A13 gene mutations.
Clinical Sensitivity: Approximately 95 percent.
Methodology: Bidirectional sequencing of the entire SLC25A13 coding region and intron/exon boundaries.
Analytical Sensitivity and Specificity: Greater than 99 percent.
Limitations: Diagnostic errors can occur due to rare sequence variations. Regulatory region mutations, deep intronic mutations, and large deletions/duplications will not be detected. Mutations in genes other than SLC25A13 are not evaluated.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online at www.aruplab.com.
Counseling and informed consent are recommended for genetic testing. Consent forms are available online.
|Component Test Code*||Component Chart Name||LOINC|
|2006262||Citrin Deficiency (SLC25A13) Seq Spcm|
|2006263||Citrin Deficiency (SLC25A13) Seq Interp|