Cerebrospinal fluid levels of myelin basic protein and creatin kinase BB as index of active demyelination

Radioimmunoassay‐determined myelin basic protein (MBP) shed to CSF during active demyelination, has been found to be a useful but non‐specific test for MS. CSF creatin kinase BB (CK‐BB), as measured by radioimmunoassay, is increased in a variety of neurological diseases, and has been considered a useful indication of brain damage but not of demyelinating diseases. Taking into account that the mean concentration of CSF CK‐BB should not be increased in patients during the acute phase of MS, we suggest that the CSF MBP/CK‐BB ratio could be a more specific index to demyelination than CSF‐MBP alone. We also defined a laboratory demyelination pattern (CSF MBP>mean control MBP + 2 S.D. and CK‐BB<MBP). CSF levels of MBP and CSF levels of CK‐BB were determined by radioimmunoassay in 232 patients with several neurological disorders and 33 control subjects. Patients diagnosed as having MS with clinical exacerbation had significantly higher values of CSF–MBP/ CSF–BB ratio than control subjects. Our study showed a significant presence of demyelination pattern in CSF of patients with MS. We conclude that the CSF MBP/CK–BB ratio and the CSF demyelination pattern may be new and reliable tests for the diagnosis of MS. Copyright © 1986, Wiley Blackwell. All rights reserved