This project is expected to answer the question of interest assays of metabolites in the CSF as a tool for early diagnosis and should show whether it is possible or not to use such markers in the blood or urine. These studies should also help shed light on the pathophysiological original early clinical disease. While ALS appears to be more a clinical syndrome that pathophysiological entity unique metabolic abnormalities identified could help identify mechanisms disrupted in which therapeutic interventions will be possible.

A blood test that would allow the diagnosis

1. to reduce the time between the first signs and diagnosis in ALS patients for therapeutic treatment earlier and
2. to exclude rapidly non ALS in their avoiding unnecessary investigations and anxiety of being infected with a terrible prognosis disease. It is currently accepted that neurodegenerative diseases such as ALS begin before the first clinical signs and the patient could benefit from a more efficient care if it was early.

Conduct a prospective study with 400 patients.

The secondary objectives are:

1. attempt to improve the predictive power of markers assays by adding new parameters
2. to check whether the assayed molecules in other environments more accessible (blood, urine) would provide equivalent diagnostic power of those assayed in the CSF
3. identify metabolic pathways disrupted early that could be related to the pathogenesis of neurodegeneration.

Inclusion Criteria:

• age 30-80
• Consent signed
• affiliation to a social security organism

Exclusion Criteria:

• Patients treated with RILUZOLE
• Enrollment in an other study