Classification matters for catatonia and autism in children.

Despite its chequered history, Kahlbaum's 1874 description of catatonia (tension insanity) and its categorization as a clinical illness is in outline still valid. Kahlbaum also acknowledged the existence of catatonia in children. Corresponding case studies have also been analyzed. The originators and disciples of the Wernicke-Kleist-Leonhard school proved catatonia in early childhood as a discrete entity with specific psychopathology. This does not mean that catatonic symptoms do not occur in other illnesses and in particular in organic psychoses. These are, however, of a totally different nature. Autism, as first described in connection with schizophrenic negativism by Bleuler in 1910, is one of the key symptoms of schizophrenia. As identified by Kanner in 1943, abnormal social interaction and communication, together with retarded development, are the main characteristics of autism in early childhood. Asperger's concept of autistic disorder (1944), although based on psychopathological theory, did not include retardation in development as an aspect. Consequently, autistic behavior can occur in a variety of mental disorders. Research into possible etiological and pathogenetic factors has been undertaken, but no clear link found as yet.