Roussy–Levy Disease

In 1926, Roussy and Levy described a large family in which the members manifested an early onset dominantly inherited gait ataxia, pes cavus, areflexia, eventually associated with distal muscle atrophy, postural tremor, and minor superficial sensory loss. Slow nerve conduction and demyelination of nerve fibers with onion bulb formations in nerve biopsy specimens led to consider the Roussy–Levy syndrome as a variant of demyelinating Charcot–Marie-Tooth disease (CMT-1). Indeed, the long term follow up of the original family and, more recently, the identification of the molecular defect in the P0 gene showed that the Roussy–Levy disease deserves its eponym since it combines original clinical, pathological, and genetic features. It also illustrates the overlaps between the phenotypes associated with the P0 and PMP22 peripheral myelin protein disorders.