Abstract
Multiple sclerosis (MS) is characterized by multiple demyelinating lesions disseminated in the central nervous system. The clinical course of MS involves acute attacks leading to permanent disability and a chronic progressive stage occurring at the beginning of the disease or after a relapsing-remitting phase. Investigations that provide supportive evidence for the diagnosis of MS are magnetic resonance imaging and cerebrospinal fluid examination. Recent pathological studies showed evidence of early axonal pathology, remyelination in some cases, and diffuse pathology. Genetic and immunological studies suggest that MS is an auto-immune disease, partially genetically determined but the role of an environmental factor, possibly infectious is possible. Cumulative evidence of the efficacy of interferon beta and other disease-modifying drug therapy has completely modified the therapeutic approach of MS.