title: Autism spectrum disorder and Klinefelter syndrome.
abstract: BACKGROUND
  Autism is a severe handicapping disorder of early childhood characterized by a distinct pattern of social and communication impairment with rigid ritualistic interests. In about 10-25% of cases, it is associated with known medical conditions. Population-based studies of autism have found that Klinefelter's syndrome (KS), a common chromosome abnormality, is sometimes associated with autism. However, few detailed case descriptions of patients with KS and autism have not been published.
  
  
  METHODS
  In this paper, we describe the occurrence of autistic features in two cases of Klinefelter syndrome, one with the typical XXY karyotype and the other with the XXYY variant.
  
  
  CONCLUSIONS
  Autistic features may be more common in persons with Klinefelter syndrome than generally believed. We propose that all patients with KS should be screened for the presence of autism.
authors.affiliation: Division of Child Psychiatry, University of Michigan Hospital, 200 East Hospital Drive, Ann Arbor, MI 48109-0277, USA.
authors.forename: P
authors.initials: P
authors.lastname: Jha
authors.forename: D
authors.initials: D
authors.lastname: Sheth
authors.forename: M
authors.initials: M
authors.lastname: Ghaziuddin
mesh_terms: D000293:Adolescent; D001289:Attention Deficit Disorder with Hyperactivity / Q000150:complications / Q000175:diagnosis; D001321:Autistic Disorder / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D002648:Child; D003147:Communication Disorders / Q000150:complications; D015897:Comorbidity; D003863:Depression / Q000150:complications / Q000175:diagnosis; D003937:Diagnosis, Differential; D005838:Genotype; D006801:Humans; D007621:Karyotyping; D007713:Klinefelter Syndrome / Q000150:complications / Q000175:diagnosis* / Q000235:genetics; D008297:Male; D008403:Mass Screening; D012918:Social Alienation; D012919:Social Behavior