Vitamin B12 metabolism in multiple sclerosis
E. H. Reynolds, T. Bottiglieri, M. Laundy, R. F. Crellin and S. G. Kirker
Department of Neurology, King's College Hospital, London, England.
We have previously described 10 patients with multiple sclerosis (MS) and
unusual vitamin B12 deficiency. We have therefore studied vitamin B12
metabolism in 29 consecutive cases of MS, 17 neurological controls, and 31
normal subjects. Patients with MS had significantly lower serum vitamin B12
levels and significantly higher unsaturated R-binder capacities than
neurological and normal controls, and they were significantly macrocytic
compared with normal controls. Nine patients with MS had serum vitamin B12
levels less than 147 pmol/L and, in the absence of anemia, this subgroup
was significantly macrocytic and had significantly lower red blood cell
folate levels than neurological and normal controls. Nine patients with MS
had raised plasma unsaturated R-binder capacities, including three patients
with very high values. There is a significant association between MS and
disturbed vitamin B12 metabolism. Vitamin B12 deficiency should always be
looked for in patients with MS. The cause of the vitamin B12 disorder and
the nature of the overlap with MS deserve further investigation. Coexisting
vitamin B12 deficiency might aggravate MS or impair recovery from MS.
