[Differential diagnosis between the autistic spectrum and the schizophrenic spectrum]

The nosological distinction between the autistic spectrum and the schizophrenic spectrum is clearly defined today, despite scientific evidence of the genetic relationship between the two conditions. The overlap between the negative symptoms of schizophrenia and certain autistic manifestations, and the fact that professionals who are not familiar with autistic spectrum disorders have misguidedly attributed positive symptoms of schizophrenia in autism together highlight the importance of deciphering the keys that make it possible to reach a differential diagnosis or to evaluate the comorbidity and co-occurrence of both spectra when this is the case.

The article analyses and unravels the manifestations of autism that could be mistaken for the psychotic dimension and the disorganisation dimension corresponding to the positive symptoms of the schizophrenic spectrum. It also seeks to clarify the psychological explanations justifying the manifestation of certain negative symptoms frequently associated with autism.

The keys to determining whether the clinical manifestations belong to the autistic spectrum, the schizophrenic spectrum or result from comorbidity lie in the evaluation of the developmental history of the person, the prodrome and onset of the condition, its course and the presence or absence of positive symptoms of schizophrenia. Determining them will play a crucial role in helping the professional to make decisions concerning both the diagnosis and treatment.