This project is an ancillary study carried out from the cohort of patients included in the HYCORE protocol PET-Scan evaluation of metabolic abnormalities associated with the clinical evolution at 6 months of patients suffering from a motor conversion disorder (RCB N°: 2014-A01159-38) of which the CHU of Nîmes is the promoter. In the HYCORE project, 20 patients suffering from a first episode of motor conversion disorder (with paralysis, motor weakness or abnormal movements according to DSM-IV criteria) in acute phase (evolving for less than one month) recruited in the neurology and psychiatry departments of the University Hospital of Montpellier and Nîmes are included.~Thinvestigtor plan to use the biological samples collected in the HYCORE project for the determination of markers of inflammation and neurofilaments (GFAP & NfL); the levels of inflammatory markers thus obtained will be put into perspective in relation to the cerebral metabolism observed by PET-scan as well as the persistence of a motor handicap (EDSS score) evaluated in the HYCORE study.
Conversion disorders, also called dissociative disorders (ICD-10), or functional neurological disorders (DSM-5), are a common condition, with a prevalence of 1-10% in medical and surgical inpatients (Toone 1990), and 10-30% in neurology patients (Carson et al. 2000).~They are characterized by the presence of symptoms or deficits affecting voluntary motor, sensory, or sensory functions suggestive of a neurological or general medical condition in combination with psychological factors. Functional neurological disorder is currently a diagnosis of elimination and its treatment remains uncodified. A better understanding of the pathophysiology of this disorder is needed to improve the diagnostic and therapeutic approach to this condition.~Identifying new biological markers associated with motor symptoms occurring during the course of the functional neurological disorder would allow clinicians to acquire new diagnostic methods, to improve therapeutic means and their specificity and to highlight possible predictive factors of the clinical evolution of this pathology. At the same time, the identification of biological markers associated with motor symptoms will allow the patient to better understand and accept the diagnosis, and thus to better adhere to the proposed treatment.