NEUROPHYSIOLOGICAL DETERMINATION OF THE CARPAL TUNNEL SYNDROME IN PATIENTS WITH CHRONIC DEMYELINATING POLYNEUROPATHY

Clerici R., De Riz M., Corrà B., Baron P.L., Scarpini E., Conti G., Scarlato G.
Department of Neurological Sciences, Univ. of Milan, IRCCS Ospedale Maggiore, Milano
The specific spinal cord lesion caused by vitamin B12 deficiency is known as subacute combined degeneration (SCD). This is a rare cause of demyelination of the dorsal and lateral columns of spinal cord and even more rarely of peripheral nerves, optic nerve and brain.
We report a case of SCD in a vegetarian 55-year-old fe- male who presented with 6 weeks history of gradually progressive paresthesia involving thoracoabdominal skin below C5 dermatome and both lower limbs and postural instability due to a mild impairment of deep sensation. Hematological tests revealed abnormal Medium Corpuscular Volume (MCV) without anaemia and low vitamin B12 levels. The cause of this deficiency was secondary to atrophic gastritis. A spinal cord MRI demonstrated two T2-weighted hyperintense signal alterations (C1-C3 and C3-C4). She was treated with parenteral vitamin B12 supplements and experienced gradual improvement in her clinical symptoms. Repeat MRI of cervical spinal cord after 5 months showed a relevant decrease in the areas of abnormal signal. In other documented cases reported in literature, there was a precocious clinical improvement, while the MRI lesions recovered with a delay. However, it is essential to recognize SCD among the different demyelinating diseases and treat it as soon as possible.