title: Inherited metabolic disorders in Turkish patients with autism spectrum disorders.
abstract: Autism spectrum disorders (ASDs) are a major health problem because of their high prevalence in the general population. The pathophysiology of ASD remains unclear, although genetic defects may be detected in 10-20% of affected patients. Among these cases, the prevalence of inherited metabolic disorders (IMD) has not been extensively evaluated. IMDs responsible for ASDs are usually identified via clinical manifestations such as microcephaly, dysmorphic features, convulsions, and hepatosplenomegaly. Infrequently, patients with no additional clinical symptoms suggestive of an IMD may be diagnosed as having an idiopathic ASD. High consanguinity rates have resulted in an increased prevalence of IMDs in the Turkish population. The aim of this study was to explore the benefits of systematic screening for IMD among Turkish patients with ASDs. In our study, data were retrospectively collected for 778 children with ASDs. In all cases, the metabolic investigations included an arterial blood gas analysis, serum ammonia and lactate levels, a quantitative plasma amino acid analysis, a whole blood acylcarnitine profile via tandem mass spectrometry and a urine organic acid profile. Urinary glycosaminoglycan levels and homocysteine levels were screened in selected cases; 300 of the 778 patients with ASDs whose physical and metabolic investigations were complete and met this study's criteria were enrolled. Among the 300 children with autism, IMD were diagnosed in nine patients as follows: two patients were diagnosed with phenylketonuria, and one patient was diagnosed with partial biotinidase deficiency; one patient was diagnosed with mucopolysaccharidosis type III, and one patient was diagnosed with classical homocystinuria; one patient was diagnosed with glutaric acidemia type 1, and one patient was diagnosed with short chain acyl-CoA dehydrogenase deficiency; one patient was diagnosed with argininemia, and one patient was diagnosed with L-2-hydroxyglutaric aciduria.
authors.affiliation: Istanbul University Cerrahpasa Medical Faculty, Department of Pediatrics, Division of Nutrition and Metabolism, Istanbul, Turkey.
authors.forename: Ertugrul
authors.initials: E
authors.lastname: Kiykim
authors.affiliation: Istanbul University Cerrahpasa Medical Faculty, Department of Pediatrics, Division of Nutrition and Metabolism, Istanbul, Turkey.
authors.forename: Cigdem Aktuglu
authors.initials: CA
authors.lastname: Zeybek
authors.affiliation: Istanbul University Cerrahpasa Medical Faculty, Department of Pediatrics, Division of Nutrition and Metabolism, Istanbul, Turkey.
authors.forename: Tanyel
authors.initials: T
authors.lastname: Zubarioglu
authors.affiliation: Istanbul University Cerrahpasa Medical Faculty, Department of Pediatrics, Division of Nutrition and Metabolism, Istanbul, Turkey.
authors.forename: Serif
authors.initials: S
authors.lastname: Cansever
authors.affiliation: Istanbul University, Cerrahpasa Medical Faculty, Department of Neurology, Istanbul, Turkey.
authors.forename: Cengiz
authors.initials: C
authors.lastname: Yalcinkaya
authors.affiliation: Istanbul University Cerrahpasa Medical Faculty, Department of Pediatrics, Division of Nutrition and Metabolism, Istanbul, Turkey.
authors.forename: Erdogan
authors.initials: E
authors.lastname: Soyucen
authors.affiliation: Istanbul University Cerrahpasa Medical Faculty, Department of Pediatrics, Division of Nutrition and Metabolism, Istanbul, Turkey.
authors.forename: Ahmet
authors.initials: A
authors.lastname: Aydin
mesh_terms: D000293:Adolescent; D000328:Adult; D000596:Amino Acids / Q000097:blood; D000641:Ammonia / Q000097:blood; D000067877:Autism Spectrum Disorder / Q000097:blood / Q000453:epidemiology* / Q000652:urine; D001784:Blood Gas Analysis / Q000706:statistics & numerical data; D002331:Carnitine / Q000031:analogs & derivatives / Q000097:blood; D002648:Child; D002675:Child, Preschool; D015897:Comorbidity; D005260:Female; D006025:Glycosaminoglycans / Q000652:urine; D006710:Homocysteine / Q000652:urine; D006801:Humans; D007223:Infant; D019344:Lactic Acid / Q000097:blood; D008297:Male; D008661:Metabolism, Inborn Errors / Q000097:blood / Q000453:epidemiology* / Q000652:urine; D015995:Prevalence; D012189:Retrospective Studies; D053719:Tandem Mass Spectrometry; D014421:Turkey / Q000453:epidemiology; D055815:Young Adult
chemical_list: D000596:Amino Acids; D006025:Glycosaminoglycans; C116917:acylcarnitine; D006710:Homocysteine; D019344:Lactic Acid; D000641:Ammonia; D002331:Carnitine
keywords: autism spectrum disorders; incidence; inherited metabolic disorders; metabolic screening