Glutarylcarnitine (C5-DC)

Test description Measurement of urine glutarylcarnitine (C5-DC) is available as an additional test for glutaric acidemia, particularly type I. While many patients with GA1 are identified via newborn screening, individuals who are considered “low excretors” may not be identified by this type of screening and by follow-up diagnostic testing. A “low excretor” will have normal or only mildly elevated biochemical analytes in the plasma, but will often have more distinctive elevations of C5-DC in the urine. Patients with glutaric acidemia type II will also typically show elevated glutarylcarnitine in urine.
Disease name Glutaric Acidemia type 1 (GA1)
Clinical info Glutaric acidemia type 1 (GA1) is an inborn error of lysine, hydroxylysine and tryptophan metabolism caused by the deficiency of glutaryl-CoA dehydrogenase (GCDH). GA1 is a neurodegenerative disorder with loss of neurons in the basal ganglia. Clinical features vary, but often include macrocephaly, gait abnormalities, hypotonia, spasms, rigidity and seizures. Retinal or subdural hemorrhages can also occur. Other than possible macrocephaly, patients appear normal at birth. Clinical features are typically preceded by an acute encephalopathic illness with fever before five years of age.
Methodology Analysis will be done by tandem mass spectrometry (MS-MS) with quantitation of creatine and creatinine.
Associated Tests Molecular analysis for the gene causing GA1 (GCDH) is also available for identification of the causative mutation within a family, carrier status and prenatal diagnosis.
Specimen Requirements Urine (at least 2ml) is requested for the analysis.
Transport Samples must be frozen and shipped on dry ice by overnight delivery services
Turnaround time 10 days
CPT Codes 82017, 83788, 82570
Cost $94.22
Contact For further information contact Kellie King, MS or Tim Wood, PhD at 1-800-473-9411

Biochemical Lab

The Biochemical Lab provides diagnostic and screening tests for a variety of inherited metabolic disorders.

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