Cerebrospinal fluid measures of disease activity in patients with multiple sclerosis.

The potential of magnetic resonance imaging to serve as a surrogate marker of disease activity in patients with multiple sclerosis (MS) is increasingly recognised. In contrast, the use of cerebrospinal fluid analysis has received less attention. We analysed the correlation between clinical data and cerebrospinal fluid parameters in 75 patients with acute optic neuritis (ON) as a possible first symptom of MS, as a symptom of clinically definite MS, and in patients with an attack of MS other than ON. The samples were obtained within 30 days from the onset of an exacerbation. The concentration of myelin basic protein (MBP) in cerebrospinal fluid was significantly correlated with the visual acuity in patients with ON and the Kurtzke EDSS score in patients with MS. The concentration of MBP in CSF also correlated positively with the CSF leukocyte count, intrathecal IgG synthesis, and the CSF-serum albumin concentration quotient. The concentration of MBP in CSF correlated negatively with intrathecal IgA synthesis. The results support the use of the concentration of MBP in CSF as a surrogate marker of disease activity during acute exacerbations of MS; the data also link the presence of MBP in CSF to neuroimmunological parameters.