Snapshot A 3-year-old boy is brought to his pediatrician by his mother due to abnormal behavior. She reports that he does not appear to respond to affection, does not look her in the eyes, and constantly lines up his toys. He becomes agitated when she tries to take him away from his toys or if the mother cooks a different meal for dinner. On physical examination, he does not respond to questions and is distracted by the texture of the exam-table cloth. Introduction Clinical definition neurodevelopmental disorder that is characterized by social communication and interaction deficit restricted repetitive patterns of behavior interest activities autism spectrum disorders (ASD) encompasses autistic disorder childhood disintegrative disorder pervasive developmental disorder-not otherwise specified asperger disorder Epidemiology Demographics more common in males Risk factors family history ETIOLOGY Pathogenesis unclear however, brain structure, connectivity, and function abnormalities have been associated with this neurodevelopmental disorder Associated conditions intellectual disability and other developmental conditions (e.g., attention deficit hyperactivity disorder) anxiety disorders behavioral disorders genetic syndromes (e.g., fragile X syndrome) Presentation Symptoms see diagnostic criteria Differential Language disorder Obsessive compulsive disorder Rett syndrome (this occurs almost exclusively in girls) Reactive attachment disorder key distinguishing factors associated with trauma and severe stressors in childhood poor ability to form social connections with others decreased positive emotions volatile emotions and mood like to control their own routine DIAGNOSIS DSM V criteria social communication and social interaction deficit in many contexts such as lack of social-emotional reciprocity lack of nonverbal communicative behaviors impairment in developing, maintaining, and understanding relationships restricted and repetitive patterns of behavior, interests, or activities such as motor movements that are stereotyped or repetitive (e.g., flipping objects) inflexibility to change restricted and fixated interests these are typically with abnormal intensity or focus hyper- or hyporeactivity or unusual interest in a sensory stimulus (e.g., fascination with lights) these symptoms must be present in the patient's early developmental period in the absence of an organic etiology (e.g., hearing dysfunction) these symptoms cannot be better explained by other conditions (e.g., intellectual developmental disorder) Treatment Conservative behavioral and educational intervention indication used to increase functional independence and quality of life Medical psychopharmacologic agents indication used for targeted symptom improvement example maladaptive behaviors (e.g., irritability, self-injury, and tantrums) aripiprazole or risperidone Prognosis Difficult to determine in early childhood and depends on many factors