Autism and autistic spectrum disorders in the context of new DSM-V classification, and clinical and epidemiological data.

Autism is one of disorders from the autism spectrum, besides Asperger syndrome, atypical autism and pervasive developmental disorder not otherwise specified. They are classified as mental disorders as being manifested by a wide range of cognitive, emotional and neurobehavioural abnormalities. Key categorical characteristics of the disorder are clear impairments of the development of the child's socialisation, understanding and production of verbal and non-verbal communication and restricted and repetitive patterns of behaviour. Demarcation boundaries are not clear, neither within the very group of the disorders from the autistic spectrum, nor with respect to the autistic behavioural features in the general population. For this reason, the term spectrum points out the significance of the dimensional assessment of autistic disorders, which will most likely be the basis of the new diagnostic classification of the disorders belonging to the current group of pervasive developmental disorders in the new DSM-V classification. The understanding, as well as the prevalence of the autistic spectrum disorders has changed drastically in the last four decades. From the previous 4 per 10,000 people, today's prevalence estimates range from 0.6 to around 1%, and the increase of prevalence cannot be explained solely by better recognition on the part of experts and parents or by wider diagnostic criteria. The general conclusion is that the autistic spectrum disorders are no longer rare conditions and that the approach aimed at acknowledging the warning that this is an urgent public health problem is completely justified.