Anevaluation ofcerebrospinal fluid oligoclonal banding confirmed byimmunofixation on agarosegel

SUMMARY The cerebrospinal fluid (CSF) from 115 consecutive patients undergoing diagnosticlumbar puncture or myelography was examined to determine the usefulness ofimmunofixation,following agarose gel electrophoresis, in the detection of oligoclonal IgG. All electrophoretic patterns were evaluated with and without immunofixation, and the interpretation of 9% ofspecimens was alteredby immunofixation. Thedemonstrationofoligoclonal IgG was shown to be more reliable in the diagnosis ofmultiple sclerosis than otherindices ofintrathecal synthesis ofIgG. It is concluded that immunofixation should be used routinely when examining CSFforoligoclonal banding. The diagnosis of multiple sclerosis on clinicalgrounds alone is often difficult and there is need for a reliable laboratory test for the disease. Thedemonstration of oligoclonal bands of IgG in the cerebrospinal fluid (CSF) hasbeenshown to be use- fulinconfirmingthediagnosis.'2 Thesebands can bedemonstratedbypolyacrylamide gel electrophoresis(PAGE),3 agarose gel electrophoresis'