Recent gains in clinical multiple sclerosis research

Abstract

Multiple sclerosis (MS) is a common neurological disease mainly affecting young people. Around the world, over 2.5 million people suffer from this central nervous system (CNS) disorder. Although the exact disease mechanism is not completely clear, it is known that both environmental and genetic factors influence the development of MS. Here we aim to summarize a few major highlights of recent progress that have been made in clinical MS research. A genetic predisposition in combination with Epstein-Barr virus infection seems to be essential to get MS. Recently more than 50 susceptibility genetic loci for MS have been described. MS prevalence has a latitudinal gradient indicating that sunlight exposure and therefore vitamin D are important contributors to MS risk. Several studies found an inverse association between MS prevalence and serum vitamin D levels. In most cases, MS starts with an acute episode involving one or more sites of the CNS. The role of the recently revised McDonald Diagnostic Criteria for the diagnosis of MS, which sometimes allow the diagnosis after a first attack, is discussed. Most patients with MS suffer from exacerbations and remissions of neurological deficits: relapsing-and remitting MS. With time, the majority of these patients enter a disease phase characterized by continuous, irreversible neurological decline; this is called secondary progressive MS. In 10-20% of patients, the disease is progressive from onset. Life expectancy of patients after diagnosis with MS is around 35 years, and MS patients die 5-10 years earlier than the general population. A substantial percentage of MS patients have their first attack during childhood. Clinics of childhood-onset MS versus adult-onset are explained, as are diagnostics, differential diagnoses and therapeutic options for children with MS. Also another demyelinating disease of the CNS, neuromyelitis optica (NMO) is highlighted. Since NMO has been considered as a variant of MS and also has been misdiagnosed as MS, recent insights in the pathology of NMO are explained.