Multiple sclerosis epidemiology, ethiopathogenesis, physiopathology and differential diagnosis [Esclerose múltipla: Epidemiologia, etiopatogenia, fisiopatologia e diagnóstico diferencial]

• Type: Article in International Scientific Journal
• Date: 2012

Authors

Pedro Abreu (Author) FMUP; Mendonca, MT (Author) Other; Joana Guimaraes (Author) FMUP; Sa, MJ (Author) Other

Journal

Title: Sinapse

Vol. 12

Pages: 5-14

ISSN: 1645-281X

Publisher: Sociedade Portuguesa de Neurologia

Indexing

Scopus - 3 Citations

Other information

Authenticus ID: P-008-8VS

Abstract (EN): The scientific advances regarding the ethiopathogenesis and physiopathology of multiple sclerosis are so fast that periodic update of concepts is awaited. Moreover, new epidemiological data and criteria improving differential diagnosis have been described. The objective of this review is to update concepts about epidemiology, ethiopathogenesis, physiopathology and differential diagnosis of multiple sclerosis. Multiple sclerosis is a chronic inflammatory demyelinating disease of the central nervous system more frequent in young ages and in the female sex, the incidence of which increases with latitude. Recent studies indicate an increase in the incidence and earlier onset in women. Although the cause of the disease is unknown, genetic and environmental risk factors have been identified. The HLA allele HLA-DRB1*15 is the genetic factor more strongly associated with the risk of developing multiple sclerosis; the better established environmental factors are the exposition to the Epstein-Barr virus, smoking and vitamin D levels. The combination of environmental factors with a certain individual genetic predisposition, discloses an immunological dysregulation. Multiple sclerosis is considered to be mediated by T cells and its physiopathology is complex, intervening various immunological factors. From adaptive immunity, it must be emphasized the role of Th17 populations, with secretion of proinflammatory cytokines, cytotoxic T CD8+ and B lymphocytes. The innate immunity also participates in multiple sclerosis immunopathogenesis, mainly through microglia activation. The action of humoral and cellular changes induces focal inflammation with demyelination and axonal damage pointing to a dual face - inflammatory and degenerative - of the disease. Despite the natural repair mechanisms leading to remyelination and axonal recovery, in later stages this ability becomes exhausted and disease progresses. The absence of specific diagnostic biomarkers for multiple sclerosis imposes the exclusion of other inflammatory diseases with neurological involvement, especially when a first demyelinating event occurs - clinically isolated syndrome. The main neurological manifestations appearing in that condition that allow to support or reject the diagnosis of multiple sclerosis are described. The characteristic clinical and paraclinical data of other idiopathic demyelinating (neuromyelitis optica, acute disseminated encephalomyelitis, acute transverse myelitis, optic neuritis) and systemic inflammatory disorders with neurological involvement (systemic erythematous lupus, Behçet's disease, Sjögren'disease) are presented. In conclusion, the knowledge of the factors that contribute to the development of multiple sclerosis and the pathological processes taking place in the nervous system favours a better understanding of the disease and the discovery of new immunotherapeutic targets. The precise diagnosis of multiple sclerosis requires a rigorous systematization of differential diagnoses.

Language: English

Type (Professor's evaluation): Scientific