Multiple Sclerosis (MS) Profile
Clinical Information Discusses physiology, pathophysiology, and general clinical aspects, as they relate to a laboratory test
Multiple sclerosis (MS) is a chronic inflammatory demyelinating disease characterized by visual, motor, and sensory disturbances. The diagnosis of MS is dependent on clinical, radiological, and laboratory findings. The detection of increased intrathecal immunoglobulin (Ig) synthesis is the basis for current diagnostic laboratory tests for MS. These tests include the cerebrospinal fluid (CSF) IgG index and CSF oligoclonal band detection.
Diagnosing multiple sclerosis, especially helpful in patients with equivocal clinical or radiological findings
Oligoclonal banding (OCB): > or =4 cerebrospinal fluid (CSF)-specific bands are consistent with multiple sclerosis (MS).
CSF IgG index: >0.85 is consistent with MS.
Abnormal CSF IgG indexes and OCB patterns have been reported in 70% to 80% of MS patients. If both tests are performed, at least 1 of the tests has been reported to be positive in >90% of multiple sclerosis patients. A newer methodology for OCB detection, isoelectric focusing, is utilized in this test and has been reported to be more sensitive (90%-95%).
The presence of OCB or elevated CSF IgG index is unrelated to disease activity.
Cautions Discusses conditions that may cause diagnostic confusion, including improper specimen collection and handling, inappropriate test selection, and interfering substances
Increased intrathecal Ig synthesis may occur in other inflammatory central nervous system diseases and, therefore, these assays are not specific for multiple sclerosis (specificity=95%).
Reference Values Describes reference intervals and additional information for interpretation of test results. May include intervals based on age and sex when appropriate. Intervals are Mayo-derived, unless otherwise designated. If an interpretive report is provided, the reference value field will state this.
CSF IgG index: 0.00-0.85
CSF IgG: 0.0-8.1 mg/dL
CSF albumin: 0.0-27.0 mg/dL
0-4 months: 100-334 mg/dL
5-8 months: 164-588 mg/dL
9-14 months: 246-904 mg/dL
15-23 months: 313-1,170 mg/dL
2-3 years: 295-1,156 mg/dL
4-6 years: 386-1,470 mg/dL
7-9 years: 462-1,682 mg/dL
10-12 years: 503-1,719 mg/dL
13-15 years: 509-1,580 mg/dL
16-17 years: 487-1,327 mg/dL
> or =18 years: 767-1,590 mg/dL
Serum albumin: 3,200-4,800 mg/dL
CSF IgG/albumin: 0.0-0.21
Serum IgG/albumin: 0.00-0.40
CSF IgG synthesis rate: 0-12 mg/24 hours
Clinical References Provides recommendations for further in-depth reading of a clinical nature
1. Andersson M, Alvarez-Cermeno J, Bernardi G, et al: Cerebrospinal fluid in the diagnosis of multiple sclerosis: a consensus report. J Neurol Neurosurg Psychiatry 1994 Aug;57(8):897-902
2. Tourtellotte WW, Walsh MJ, Baumhefner RW, et al: The current status of multiple sclerosis intra-blood-brain-barrier IgG synthesis. Ann NY Acad Sci 1984;436:52-67