According to the Association for Research on ALS, amyotrophic lateral sclerosis (ALS), better known as Charcot disease, affects 8,000 patients in France.
Its annual incidence is 2.7 cases per 100,000 inhabitants. It is a rare neurodegenerative pathology characterized by the destruction of neurons responsible for motor skills, motor neurons.
A surprising story of a village in the Somma
In the Somme, the village of Saint-Vast-en-Chaussy is in shock after 5 deaths since 2009 from Charcot disease. Residents of the same town, these people also all lived on the same street.
The town’s mayor contacted the Hautes-de-France regional health agency to alert him. “Five cases of residents, living on the same street or perpendicular to one of them, were confirmed to have contracted the disease between 2007 and 2022”, notes Destination Sainte to the ARS, which continues: “Study report to the ARS This allowed the confirmation of high cases of ALS in the municipality”.
Public Health France was contacted to determine if there was a cluster of Charcot disease in Saint-Vast-en-Chaussy.
“The epidemiologic objectives of responding to suspected clusters are to determine whether there is in fact a statistical excess of disease in the observed population and to determine whether there are one or more local causes for this cluster of cases, other than chance, that can be acted upon. ,” explains the National Public Health Agency.
“At this stage, the investigation is ongoing. Their first objective is to carefully document the cases. This documentation is an essential first step in investigating the cluster,” the agency continues.
Example of Montchevin, in Savoy
“It is not exceptional in itself but it is still a source of high incidence”, notes Timothée Langlet, neurologist at the Hospital Petit-Salpêtrière, in Destination Sainte.
“There are many cases in a limited geographical area, we have already seen that. Two cases in the same street, in the same building, even within a couple. This is often attributed to chance, but we know that there may be environmental factors that can influence the risk of developing ALS-type disease. And that’s why it’s important to be concerned about this kind of situation because the investigation will be able to shed light on factors that we don’t yet know about.
The expert recalls that in 2021, an unusually high number of victims of Charcot disease – 14 cases per 900 inhabitants in 22 years – was observed in Savoie in the village of Montchavin.
An epidemiological study, the results of which were published in the Journal of Neurological Sciences, showed that consumption of the mushroom, giant gyromitra, was responsible for the cluster.
Multifactorial causes
According to Inserm, no environmental factor has been formally published. However, “tobacco, high levels of sport, exposure to pesticides, heavy metals or toxins present in certain algae (BMAA cyanotoxin) are also suspected”.
A genetic mutation would also be involved, i.e. a “random (and not transmitted) mutation of the causative gene or one or more susceptibility genes (which increases the risk of developing the disease)”.
“These environmental factors increase the risk of developing neurological disease associated with individual susceptibility factors,” Dr. adds Langlett. And we do not know how to clearly establish the role of these environmental factors in the occurrence of the disease compared to the congenital factor.
Symptomatic management
The disease usually occurs between the ages of 50 and 70. ALS is a progressive pathology that leads to death within 3 to 5 years after the first signs. It mostly damages the respiratory muscles which leads to the death of the patient.
It may first manifest itself as difficulty in articulating or swallowing in 30% of cases. Otherwise, the disease can begin “by Weakness and discomfort in the arms, legs or hands that manifest themselves at the beginning of the disease.
Then, the disease progresses:
- Contractions, stiffness of muscles and joints;
- Muscle wasting and coordination problems cause difficulty walking, grasping objects, and swallowing or speaking
- In advanced stages of the disease, the respiratory muscles are no longer able to do their job.
To date, there is no curative treatment for Charcot disease. This care is therapeutic and multidisciplinary: “Technical assistance to deal with motor disorders, physiotherapy and anti-spastic drugs, muscle relaxants and analgesics for pain, management of malnutrition, speech therapy for speech and swallowing disorders, psychological support.. .”, Inserm lists.
note down : ALS is also familial in about one in 10 cases.
