In a new study, researchers have validated a new antibody test to diagnose multiple sclerosis. The findings may represent a cost savings as well as an automated alternative to the arsenal of tests used to diagnose MS.

An antibody typically consists of two immunoglobulin heavy chains and two light chains. There are two types of light chains: kappa and lambda. The validated test measures kappa immunoglobulin free light chains in cerebrospinal fluid. 

The Mayo Clinic study analyzed serum samples from a retrospective cohort of 702 Mayo patients to determine a diagnostic value for measurement of kappa free light chains. Samples from a prospective cohort of 657 Mayo patients were used to validate that value. Of the more than 1,300 patients, 12 percent were diagnosed with MS. Researchers concluded the test is a valid alternative to a commonly used test to detect oligoclonal bands in cerebrospinal fluid. 

Oligoclonal bands are proteins that indicate inflammation of the central nervous system. The diagnostic test that detects oligoclonal bands in cerebrospinal fluid requires about four hours of analytical processing. This test is labor-intensive and involves subjective visual interpretation. 

The Mayo Clinic study validates a diagnostic value of 0.1 milligrams per deciliter to measure kappa free light chains. The study's results are comparable to diagnostic values from tests measuring oligoclonal bands. The study estimates a significant cost savings for the new test and results are available in about 20 minutes.

The findings were published in Mayo Clinic Proceedings.