The importance of early diagnosis of multiple sclerosis.

OBJECTIVE To describe the current understanding of the diagnosis and treatment of multiple sclerosis (MS) and to explore the use of magnetic resonance imaging (MRI) assessment as a prognostic tool and an indicator in the diagnosis of MS. SUMMARY MS is a chronic, progressive, demyelinating disease of the central nervous system that is associated with a significant economic burden. At this time, immunomodulatory agents (interferon beta-1a (IFNbeta-1a) [Avonex], IFNbeta-1a [Rebif], IFNbeta-1b [Betaseron], and glatiramer acetate [Copaxone]) are first-line agents, which are reported to reduce relapse rates. The diagnostic criteria for MS have evolved over time to include MRI findings as an integral part of the diagnosis. However, the most recent criteria (McDonald) are focused on the diagnosis of definite MS and do not address the status of patients with a first demyelinating event (clinically isolated syndrome [CIS]). This is an important issue because a CIS is highly predictive of developing further inflammation and definite MS when the episode occurs in conjunction with lesions on the initial MRI. Many times, MRI findings do not correlate with clinical symptoms, and clinically silent lesions are identified. Therefore, the use of MRI is salient to the early diagnosis of high-risk patients. The evolution of thought concerning early treatment in MS is based on an increased understanding of the pathology of the disease. Axonal loss occurs early in the disease process, and both white matter and gray matter are affected. Studies that have analyzed early treatment in patients highly likely to have MS (clinically isolated events with evidence of lesions on MRI) report significant benefits in delaying further changes on MRI and further attacks. Patients who begin treatment later do not reap the same benefits as those who begin treatment earlier during the disease course. CONCLUSION Patients with clinically isolated events should be referred promptly to a neurologist for assessment, including MRI scans. An early recognition of the inflammatory process enables patients to begin treatment with an immunomodulatory agent even before the technical diagnosis of definite MS so that the degenerative progression of MS can be retarded.