Isoelectric focusing of CSF proteins and the future evolution of multiple sclerosis: a clinical follow-up.

A clinical follow-up covering a period of 5-10 years after onset was performed in 150 patients with optic neuritis or other potential onset symptoms of MS. Thin-layer isoelectric focusing had been used for the initial CSF-protein analysis. No evidence for a more probable alternative diagnosis appeared in 147 patients while a non-MS diagnosis was established in 3 patients. Among these 147 subjects the planned follow-up was accomplished in 131 patients, but not in 16. An evolution into clinically definite MS occurred in 59 subjects, in whom oligoclonal CSF immunoglobulin was found in 92%. Further clinical activity without spatial dissemination--i.e. lesser degrees of diagnostic probability for MS--were found in 35 patients in whom oligoclonal CSF immunoglobulin components were detected in 86%. Among the 131 patients with a complete follow-up, 45 remained free from further clinical activity; oligoclonal CSF immunoglobulin components occurred in 40% of these patients. The frequency of further clinical activity with or without spatial dissemination was significantly higher in subjects exhibiting oligoclonal CSF immunoglobulin components than in those without such changes.