Porphyrinuria in childhood autistic disorder is not associated with urinary creatinine deficiency.

Background: Urinary metabolite measurements are often normalized to levels of the ubiquitous metabolite creatinine (CRT) to take account of variations in fluid export. Following CRT normalization, excesses of porphyrins and isoprostanes have been reported in the urines of children with neurodevelopmental disorders. It was suggested (Whiteley et al.

Porphyrinuria in childhood autistic disorder: implications for environmental toxicity.

To address a possible environmental contribution to autism, we carried out a retrospective study on urinary porphyrin levels, a biomarker of environmental toxicity, in 269 children with neurodevelopmental and related disorders referred to a Paris clinic (2002-2004), including 106 with autistic disorder. Urinary porphyrin levels determined by high-performance liquid chromatography were compared between diagnostic groups including internal and external control groups. Coproporphyrin levels were elevated in children with autistic disorder relative to control groups.