From the Guidelines
Autism Spectrum Disorder (ASD) is a neurodevelopmental disorder characterized by difficulties in social communication and interaction, and restricted or repetitive behaviors and interests.
Key Characteristics of ASD
- Difficulties in communication and relationships
- Unusually narrow interests
- Strongly repetitive, restrictive patterns of behaviour
- Atypical sensory perception, occurring in up to 90% of autistic individuals 1
- Superior attention to detail, heightened ability to systemize, and enhanced perceptual functioning 1
Diagnostic Criteria
The diagnosis of ASD is based on two symptom dimensions:
- Deficits in social communication/interaction (SCI)
- The presence of restricted/repetitive behaviors (RRBs) 1
Clinical Presentation
ASD is a heterogeneous disorder, with significant variability in cognitive level, ranging from severely impaired to very superior ability 1.
- Intellectual disability is present in approximately 30% of ASD cases
- Co-occurring medical and mental health conditions are common, including seizure disorder, gastrointestinal problems, attention-deficit/hyperactivity disorder (ADHD), anxiety, and other conditions 1
Early Identification and Intervention
Early identification of ASD is crucial, and research has identified potential early markers, including:
- Atypical body movements and motor development
- Temperamental profile
- Repetitive behavior with objects 1 Early intervention can significantly impact the outcome for children with ASD, and future research should examine biological and behavioral heterogeneity as moderators of individual responses to interventions 1
From the Research
Definition and Characteristics of Autism Spectrum Disorder (ASD)
- Autism Spectrum Disorder (ASD) is a complex and heterogeneous neurodevelopmental condition characterized by a range of social, communicative, and behavioral challenges 2.
- It is a set of neurodevelopmental disorders characterized by a deficit in social behaviors and nonverbal interactions, such as reduced eye contact, facial expression, and body gestures in the first 3 years of life 3.
- ASD is generally manifesting in the first few years of life and tending to persist into adolescence and adulthood, characterized by deficits in communication and social interaction and restricted, repetitive patterns of behavior, interests, and activities 4.
Etiology and Pathogenesis of ASD
- ASD is a disorder with multifactorial etiology, resulting from genetic and non-genetic risk factors and their interaction 3, 4.
- Genetic studies of ASD have identified mutations that interfere with typical neurodevelopment in utero through childhood, involving complexes of genes that have been involved in synaptogenesis and axon motility 3.
- Subtle anatomical and functional differences have been observed in post-mortem, neuroimaging, and electrophysiological studies, although gross brain pathology is not characteristic of autism 5.
Diagnosis and Treatment of ASD
- The diagnosis of ASD involves screening and diagnostic tools, along with an explication of genetic testing in ASD 4.
- Psychosocial interventions in children can improve specific behaviors, such as joint attention, language, and social engagement, that may affect further development and could reduce symptom severity 5.
- Educational and behavioral treatments have been the mainstay of the management of ASD, while pharmacological and interventional treatments have also shown some benefit in subjects with ASD 3.