CSF myelin basic protein levels in acute optic neuritis and multiple sclerosis.

Normal CSF-MBP levels as determined by a RIA were less than 6.2 ng/ml CSF (mean 3.9). Eighty percent of patients with acute optic neuritis have CSF-MBP levels greater than 6.2 ng/ml (mean 7.6 ng/ml CSF). Five of 7 patients with acute internuclear ophthalmoplegia due to an initial exacerbation of demyelination have CSF-MBP levels above 6.2 ng/ml (mean 6.8 ng/ml). Fifty percent of MS patients with chronic progressive disease have CSF-MBP levels above 6.2 ng/ml (mean 6.7 ng/ml). MS patients experiencing monosymptomatic exacerbations show elevated CSF-MBP levels in 75% in 75% of cases (mean 8.2 ng/ml). MS patients experiencing polysymptomatic exacerbations show significantly higher levels of CSF-MBP (mean 22.3 ng/ml) than the patients with monosymptomatic exacerbations. Ninety-five percent of MS patients experiencing polysymptomatic exacerbations have elevated levels of CSF-MBP.