Clinical Pearl The Diagnosis of Multiple Sclerosis

Introduction Multiple sclerosis (MS) is a relatively common disorder affecting between 250 000 to 350 000 people in the US alone [1, 2]. The age of onset is typically between 20 to 40 years of age with a 2:1 predominance of females over males [2]. Although the exact etiology remains unknown, current data suggest both genetic and environmental influences [3]. The underlying pathophysiology of MS is widely believed to be autoimmune in nature [1-3]. The clinical symptoms are the result of plaques of demyelination within the central nervous system (CNS) with relative preservation of the axons. The myelin sheath around axons is crucial for transmission of information between regions within the CNS. Thus, the clinical symptoms of MS are determined by the exact neuroanatomical location of the plaque.