The concomitant involvement of both the peripheral and central nervous system myelin is rare and may occur in the course of inherited lysosomal storage diseases. In inflammatory autoimmune diseases of the peripheral nervous system or CNS, a mild involvement of central or peripheral myelin has sometimes been reported.1 2 In such conditions, a single pathogenetic mechanism has been tentatively considered as responsible for the nervous tissue damage and the association of peripheral nervous system and CNS demyelinating disorders due to different pathogenetic mechanisms has never been reported.

We describe two patients with definite multiple sclerosis and hereditary peripheral neuropathy of Charcot-Marie-Tooth type 1A (CMT1A).

Patient 1, a 38 year old woman, was admitted to hospital because of episodes of gait disturbances and optic neuritis. Neurological examination showed ataxia, lower limb weakness, bilateral Babinski’s sign, increased tendon reflexes, mild sensory loss in all four limbs, impaired bladder function, …