Glutaric acidemia type I is an autosomal recessive disorder in which the body is unable to process certain proteins properly. Mutations in the GCDH gene cause glutaric acidemia type I. The GCDH gene provides instructions for making the enzyme glutaryl-CoA dehydrogenase. This enzyme is involved in processing the amino acids lysine, hydroxylysine, and tryptophan. Mutations in the GCDH gene prevent production of the enzyme or result in the production of a defective enzyme that cannot function. This leads to excessive levels of these amino acids which results in damage to the brain, particularly the basal ganglia, which are regions that help control movement. Intellectual disability may also occur.
The severity of glutaric acidemia type I varies widely; some individuals are only mildly affected, while others have severe problems. In most cases, signs and symptoms first occur in infancy or early childhood. Babies with glutaric acidemia type I are born with unusually large heads (macrocephaly). Affected individuals may have difficulty moving and may experience spasms, jerking, rigidity, or decreased muscle tone. In some cases patients developeded bleeding in the brain or eyes that could be mistaken for the effects of child abuse. Strict dietary control may help limit progression of neurological damage. Stress caused by infection, fever or other demands on the body may lead to worsening of the signs and symptoms.
Glutaric acidemia type I occurs in approximately 1 of every 30,000 to 40,000 individuals. It is much more common in the Amish community and in the Ojibwa population of Canada, where up to 1 in 300 newborns may be affected.
Methodology: Sequencing analysis
Purpose: Confirmation of Clinical Diagnosis
ICD-10 Code E72.3
Test Requisition: Sequencing Requisition
CPT Code: 81406 Cost: $863.00
Turn-around-time: 14 days
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