Biochemical studies in a patient with defects in the metabolism of acyl-CoA and sarcosine: another possible case of glutaric aciduria type II

Abstract

The clinical and biochemical abnormalities in a neonate, who died in coma accompanied by severe hypoglycaemia at the age of 3 days, are described. The study of the urinary metabolic profiles of organic acids and amino acids revealed that the excretion rates of glutaric acid, isovaleric acid, isovalerylglycine, 3-hydroxyisovaleric acid and isobutyric acid were very high. Increased excretion rates were also found for 2-methylbutyric acid, adipic acid, caproylglycine, 5-hydroxycaproic acid, caproic acid and butyric acid. The amino acid, sarcosine, was excreted in enhanced amounts and the patient had lactic aciduria, whereas the excretion of 3-hydroxybutyric acid was only moderately increased. This abnormal excretion pattern is consistent with a defect in the metabolism of acyl-CoAs and sarcosine. Normal activity of glutaryl-CoA dehydrogenase was found, excluding glutaryl-CoA dehydrogenase deficiency (glutaric aciduria type I).