Glutaric acidemia, type 1 (GA1) is an autosomal recessive inborn error of lysine, hydroxylysine and tryptophan metabolism caused by the deficiency of glutaryl-CoA dehydrogenase (GCDH). Patients are often identified via newborn screening. However, some patients are low excretors and can exhibit normal or mildly elevated biochemical analytes making a definitive diagnosis of GA1 difficult without molecular analysis. 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.