title: Porphyrinuria in childhood autistic disorder: implications for environmental toxicity.
abstract: 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. Elevation was maintained on normalization for age or to a control heme pathway metabolite (uroporphyrin) in the same samples. The elevation was significant (P < 0.001). Porphyrin levels were unchanged in Asperger's disorder, distinguishing it from autistic disorder. The atypical molecule precoproporphyrin, a specific indicator of heavy metal toxicity, was also elevated in autistic disorder (P < 0.001) but not significantly in Asperger's. A subgroup with autistic disorder was treated with oral dimercaptosuccinic acid (DMSA) with a view to heavy metal removal. Following DMSA there was a significant (P = 0.002) drop in urinary porphyrin excretion. These data implicate environmental toxicity in childhood autistic disorder.
authors.affiliation: Laboratoire Philippe Auguste, Paris, France.
authors.forename: Robert
authors.initials: R
authors.lastname: Nataf
authors.forename: Corinne
authors.initials: C
authors.lastname: Skorupka
authors.forename: Lorene
authors.initials: L
authors.lastname: Amet
authors.forename: Alain
authors.initials: A
authors.lastname: Lam
authors.forename: Anthea
authors.initials: A
authors.lastname: Springbett
authors.forename: Richard
authors.initials: R
authors.lastname: Lathe
mesh_terms: D000284:Administration, Oral; D000293:Adolescent; D001321:Autistic Disorder / Q000175:diagnosis / Q000209:etiology / Q000652:urine*; D015415:Biomarkers / Q000652:urine; D002614:Chelating Agents / Q000008:administration & dosage / Q000627:therapeutic use; D002648:Child; D002659:Child Development Disorders, Pervasive / Q000175:diagnosis / Q000209:etiology / Q000652:urine*; D002675:Child, Preschool; D002851:Chromatography, High Pressure Liquid; D003306:Coproporphyrins / Q000652:urine; D004781:Environmental Exposure / Q000009:adverse effects / Q000032:analysis*; D005260:Female; D000075322:Heavy Metal Poisoning; D006801:Humans; D008297:Male; D019216:Metals, Heavy / Q000037:antagonists & inhibitors / Q000652:urine; D011164:Porphyrias / Q000150:complications / Q000652:urine*; D011166:Porphyrins / Q000652:urine; D012189:Retrospective Studies; D004113:Succimer / Q000008:administration & dosage / Q000627:therapeutic use; D016896:Treatment Outcome; D014578:Uroporphyrins / Q000652:urine
chemical_list: D015415:Biomarkers; D002614:Chelating Agents; D003306:Coproporphyrins; D019216:Metals, Heavy; D011166:Porphyrins; D014578:Uroporphyrins; C513117:precoproporphyrin; C034350:pentacarboxylic porphyrin; D004113:Succimer