[Autism of unknown aetiology]

To review the origin, development and present state of autism, pervasive developmental disorders, progress in diagnostic tools, genetic advances, neurobiological bases, the possible causes of the increased prevalence of autism and the present treatment of the autistic condition.

Autism is a neurobiological, life-long disorder characterized by abnormal social skills, deficient verbal and not verbal communication, symbolic and imaginative play, reasoning and related complex behaviour. Autism is 4 times more frequent in males. 70% are mentally retarded (30% mild and the rest moderate and severely retarded). Approximately 25% have convulsions and around 65% inspecific EGG abnormalities. Other conditions like ADHD, anxiety, depression may be associated. RMN: increased subarachnoidal spaces, moderate ventricular enlargement, 20% have megaloencephaly. PET and 31 PMMR show increased glucose metabolism and decreased functional links with association cortex. Mental level and language are the best prognostic indices for outcome. Pathology: reduced size of nerve cells in hippocampus, subiculum, sections of the amygdala, mamillary bodies, medial septal nucleus, decreased size of cerebellar hemispheres, posterior vermis, VI VII neocerebellar lobules. Evolution: in a small group about 9-31% live independently, 11-50% attend college.

Autism is a disorder of multi-factorial origin with a genetic polygenic component and the influence of environmental elements. Treatment with risperidone improves symptoms.