Vitamin B12 neuropathy

—A minority of patients with vitamin B12 deficiency develop a neuropathy due to symmetrical damage to the peripheral nerves and posterior and lateral columns of the spinal cord, the legs being more affected than the arms. Psychiatric abnormalities and visual disturbance may also occur. Men are more commonly affected than women. The neuropathy may occur in the absence of anaemia. Psychiatric changes and at most a mild peripheral neuropathy may be ascribed to folate deficiency.

Reff: ABC OF CLINICAL HAEMATOLOGY: Second Edition