ARSACS (Autosomal recessive spastic ataxia of Charlevoix-Saguenay)

ARSACS is considered one of the most common recessive ataxias worldwide. The causative variants of this pathology, located in the SACS gene, were first described in the Charlevoix and Saguenay-Lac-St-Jean regions of Quebec (Canada). Today, it is not limited to these regions alone; cases have been reported throughout Europe and Asia.

The incidence of ARSACS in Quebec is approximately 1 case in 1,900 births.

Generally the first symptoms appear between 12-18 months of age. Initially the pathology usually presents with cerebellar ataxia and spasticity. Most patients stop being able to walk in the fifth decade of their lives.

Other frequent symptoms are:

• Neurological: slurred speech, plantar extension response, involuntary eye movement.
• Neuromuscular: loss of muscle mass, spasms, muscle weakness, instability at the onset of the disease.
• Other: hypertrophy of myelinated retinal fibers and pes cavus.

Since no cure is currently available, available treatments are aimed at alleviating neuromuscular problems. Physiotherapy and certain medications, such as baclofen, can help improve early symptoms such as spasticity (stiff and tight muscles) by helping to prevent tendon shortening and joint contractures. It has been observed that regular physical training in ARSACS patients may help them retain, and even regain, their independence of movement. Speech training may also be effective in treating speech problems.