Profiles of ultraviolet-absorbing components of urine from autistic children, as obtained by high-resolution ion-exchange chromatography.

Urines from 19 autistic children (3 female, 16 male) were analyzed by high-resolution, high-pressure anion-exchange chromatography. The results showed abnormalities in the excretion of hippuric acid, 4-hydroxyhippuric acid, and N1-methyl-2-pyridone-5-carboxamide, the end product of the nicotinic acid pathway. Considerations as the metabolic origin on the 4-hydroxyhippuric acid are discussed and related to the possibility of bacterial action and malabsorption.