We searching for a long time a blood biomarker, which would facilitate the diagnosis and better know the prognosis of the disease. The latter is very variable from one individual to another, ranging from a few months to more than 40 years.

The development of the Simoa method, a new technique for detecting very low concentrations of a molecule, the blood test of the light chain of neurofilaments (sNfL) makes it possible to better specify the prognosis in a study of 198 patients, collected from the first consultation in the center of Montpellier. We were able to show that, compared with the other prognostic factors of the disease, weight loss, the site of onset (bulbar or spinal), respiratory parameters and level of disability, the rate of sNfL was an independent predictor of survival and significantly more significantly than the other factors. For example, subjects with sNfL <71pg / ml were all alive 5 years after collection!

We have begun work to better specify the contribution of this assay to the diagnosis of the disease, which requires to study a much larger number of subjects.