CANVAS, a sensory neuronopathy to look for in ataxia.

Sensory neuronopathies name the degeneration of peripheral sensory neurons in dorsal root ganglia. Among the genetic causes, CANVAS could be the most frequent. CANVAS is a clinical entity associating cerebellar ataxia, sensory neuronopathy and vestibular areflexia due to biallelic expansions in RFC1. This study reports the 18 individuals with sensory neuronopathy tested for RFC1 expansion in our center. The clinical picture showed that chronic cough was a frequent sign beginning before the onset of other symptoms. CANVAS is an underestimated cause of late-onset sensory and cerebellar ataxia that needs to be tested for widely now that the molecular cause is known.