Used primarily as a biomarker in clinical diagnostics, especially for the detection of glutaric aciduria type I, a rare inherited metabolic disorder. Elevated levels in urine or blood indicate a deficiency in the enzyme glutaryl-CoA dehydrogenase, enabling early diagnosis and intervention in newborns. Also utilized in research settings to study metabolic pathways involving lysine and tryptophan degradation. Its presence helps assess mitochondrial function and metabolic imbalances in organic acidemias.