Detection of oligoclonal immunoglobulins in the cerebrospinal fluid by immunofixation electrophoresis.

Many disorders of the central nervous system are associated with increased concentration of cerebrospinal fluid protein due to either an increase in the permeability of blood-brain barrier or the synthesis of immunoglobulins within the central nervous system. Immunofixation electrophoresis was used to detect the immunoglobulins in sera and cerebrospinal fluid in patients with different central nervous system disorders. A strong oligoclonal band, or a single weak monoclonal band, observed in the cerebrospinal fluid but not in the serum, indicates the endogenous immunoglobulin synthesis. In 17 cases of non-infectious central nervous system diseases, we diagnosed one case of progressive multifocal leukoencephalopathy, one case of multiple sclerosis, one case of Guillain-Barre syndrome, and one case of epilepsy. A weak band was observed in both serum and cerebrospinal fluid samples in two cases of cerebral trauma. Out of 25 cases of infectious central nervous system diseases, two cases of nervous system syphilis were positive only in cerebrospinal fluid samples, and 23 cases were negative in both samples. Compared with the standard immunofixation, the application of an enzyme-labeled antibody can significantly increase the sensitivity of the method.