Normal range: up to 0.70 Index
Comment: Multiple sclerosis is relapsing and remiting demyelinating disease of the central nervous system for which there are no specific diagnostic laboratory tests. About 50% of multiple sclerosis patients have elevated CSF protein levels and about 75% have increased gamma globulin. Several tests have been devised to determine if the elevated gamma globulin is the result of intrathecal IgG synthesis. The most useful tests to aid in the diagnosis of multiple sclerosis are detection of oligoiclonal bands in the CSF and estimations of the intrathecal synthesis of IgG. The detection Oligoclonal bands is the most helpful of the laboratory tests. Synthesis of IgG in the central nervous system is typically Oligoclonal, for reasons that are unknown. Estimates of intrathecal protein synthesis include calculations of IgG index. CSF IgG index, and the IgG synthesis rate. All methods require quantitation of serum and CSF albumin and IgG The most helpful of the estimates of intrathecal protein synthesis is the IgG index. An abnormal IgG index or IgG synthesis rate (indicative of increased CSF IgG production) is noted in some 90% of cases of clinically definite MS. The IgG synthesis rate is a complex formula which provides no more useful clinical information than the IgG index
Sample: CSF, serum