CEREBROSPINAL-FLUID IN THE DIAGNOSIS OF MULTIPLE-SCLEROSIS - A CONSENSUS REPORT

The Committee of the European-Concerted Action for Multiple Sclerosis (Charcot Foundation) organised five workshops to discuss CSF analytica l standards in the diagnosis of multiple sclerosis. This consensus rep ort from 12 European countries summarises the results of those worksho ps. It is hoped that neurologists will confer with their colleagues in clinical chemistry to arrange the best possible local practice. The m ost sensitive method for the detection of oligoclonal immunoglobulin b ands is isoelectric focusing. The same amounts of IgG in parallel CSF and serum samples are used and oligoclonal bands are revealed with IgG specific antibody staining. Ah laboratories performing isoelectric fo cusing should check their technique at least annually using ''blind'' standards for the five different CSF and serum patterns. Quantitative measurements of IgG production in the CNS are less sensitive than isoe lectric focusing. The preferred method for detection of blood-CSF barr ier dysfunction is the albumin quotient. The CSF albumin or total prot ein concentrations are less satisfactory. These results must be interp reted with reference to the age of the patient and the local method of determination. Cells should be counted. The normal value is no more t han 4 cells/mu l. Among evolving optional tests, measurement of the co mbined local synthesis of antibodies against measles, rubella, and/or varicella tester could represent a significant advance if it offers hi gher specificity (not sensitivity) for identifying chronic rather than acute inflammation. Other tests that may have useful correlations wit h clinical indices include those for oligoclonal free light chains, Ig M, IgA, or myelin basic protein concentrations.