The majority of the studies exploring the measurement of FLCs as an alternative marker of intrathecal immunoglobulin synthesis have focused on MS.
MS is an autoimmune inflammatory disease of the CNS, characterised by myelin loss, axonal pathology, and progressive neurologic dysfunction . The majority of patients will first present with what is termed a clinically isolated syndrome (CIS). However, over a period of 20 years, about 60% of patients will suffer a second demyelinating event and progress to a diagnosis of clinically definite MS . The diagnosis of MS is made primarily on the basis of medical history and physical examination, with Magnetic Resonance Imaging (MRI) used to identify neurological lesions . Positive CSF findings (ie. 2 or more oligoclonal bands, or an elevated IgG index) can be important in supporting the inflammatory demyelinating nature of the condition, evaluating alternative diagnoses, and predicting clinically definite MS .