[Elevated C5-DC Acylcarnitine]
Glutaryl-CoA Dehydrogenase Deficiency (GA-1)
Differential Diagnosis: Glutaric Acidemia (GA-1).
Condition Description: GA-1 is caused by a defect of glutaryl-CoA dehydrogenase which limits metabolism of glutaryl-CoA, resulting in increased glutaric acid (toxic) and its metabolites.
MEDICAL EMERGENCY - TAKE THE FOLLOWING IMMEDIATE ACTIONS:
- Contact family IMMEDIATELY to inform them of the newborn screening result
- Consult with pediatric metabolic specialist
- Evaluate the newborn for macrocephaly and muscle hypotonia, initiate confirmatory/diagnostic testing as recommended by metabolic specialist
- Refer to metabolic specialist to be seen as soon as possible, but not later than three (3) weeks
- Educate family about diagnostic possibilities, complexity of diagnostic work-up and the possibility of neurodegenerative crisis with an intercurrent infectious illness
- IMMEDIATE treatment with IV glucose is needed for intercurrent infectious illness
- Report findings to state newborn screening program (Carleigh Soule at 307-777-6297)
Diagnostic Evaluation: Urine organic acid analysis will reveal elevated glutaric acid and 3-hydroxyglutaric acid which should be ordered promptly and is often diagnostic. If urine organic acids don’t confirm the diagnosis, the metabolic specialist will consider analyzing glutarylcartinine in urine and 3-hydroxyglutaric acid in blood and CSF, enzyme assay in fibroblasts, and molecular analysis of the GCDH gene.
Clinical Expectations: The neonate with Glutaric Acidemia Type I is usually macrocephalic but otherwise asymptomatic. Later signs include metabolic ketoacidosis, failure to thrive, and sudden onset of dystonia and athetosis due to irreversible striatal damage. With appropriate treatment, 60-70% of patients will not suffer neurodegenerative disease.
Additional Information: (Click on the name to take you to the website)
Genetic Home Reference Wyoming Department of Health
Gene Tests Colorado Newborn Screening
New England Consortium American Academy of Pediatrics
For Algorithm: http://www.acmg.net/resources/policies/ACT/Visio-C5-DC(4-29-06).pdf