NEUROLOGICAL COMPLICATIONS OF ACQUIRED COBALAMIN DEFICIENCY - CLINICAL ASPECTS

Cobalamin (Cbl, vitamin B-12) deficiency of the nervous system is a chronic progressive disorder characterized by abnormalities of the spinal cord, peripheral nerves, optic nerves and cerebrum. Initial reports of the nervous system disorder in the late nineteenth and early twentieth centuries emphasized severe spinal cord disease (Lichtheim, 1887; Russell et al, 1900). Later authors attributed the neurological features to peripheral neuropathy (Hamilton and Nixon, 1921; Pallis and Lewis, 1974). Most patients appear to have features consistent with both myelopathy and peripheral neuropathy (Healton et al, 1991). In this review we will use the term 'Cbl neuropathy' to refer to the neurological complications of Cbl deficiency, including spinal cord, peripheral nerve and cerebral damage. We believe that Cbl neuropathy better encompasses the diverse manifestations of Cbl deficiency than other terms, such as 'combined systems disease' and 'subacute combined degeneration'.