Spinal muscular atrophy type I: clinical and pathophysiological aspects/Atrofia muscular espinhal tipo I: aspectos clinicos e fisiopatologicos

Objective: To produce a literature review about etiology, diagnosis, treatment and future perspectives around spinal muscular atrophy type I (Werdnig-Hoffmann disease). Methods: Using databases like Medline, Lilacs and Scielo; the most important articles about this issue were chosen, using the keywords: spinal muscular atrophy; spinal muscular atrophy of childhood; neuromuscular diseases; spinal cord diseases; Werdnig-Hoffmann disease. Results: 68 articles were collected. After analysis process, 43 studies which focus on the clinical and/or pathophysiological aspects, were selected. Discussion: Werdnig-Hoffmann disease, the spinal muscular atrophy type I, is a hereditary disorder that causes progressive hypotony and muscular weakness. This process evolves with the loss of essential functions, resulting in high and early mortality. The spinal muscular atrophies are neuromuscular diseases characterized by degeneration of lower motor neurons. They are transmitted following the pattern mendelian autosomal recessive. The clinic signs are: hypotony, atrophy, muscular weakness and decrease or absence of osteotendinous reflexes. Treatment includes supportive care and specific medication, Nusinersen (Spinraza[R]), administered by intrathecal injection, and can delay or even stop disease progression if started early. Conclusions: The sickness has similar features on most cases and worsens sorely. However, the intensive and immediate treatment, with the specific medication and the multidisciplinary team--can promote a better quality of life to patients. Keywords: Muscular atrophy, spinal/physiopathology; Spinal muscular atrophies of childhood/physiopathology; Neuromuscular diseases; Spinal cord diseases/physiopathology. Objetivo: Realizar uma revisao bibliografica sobre a etiologia, diagnostico, tratamento e perspectivas futuras sobre a atrofia muscular espinhal tipo I (doenca de Werdnig-Hoffmann). Metodos: Utilizando o banco de dados Medline, Lilacs e Scielo, os artigos mais relevantes foram selecionados, por meio das palavras-chave: atrofia muscular espinhal; atrofia muscular espinhal infantil; doencas neuromusculares; doencas da medula espinhal; doenca de Werdnig-Hoffmann. Resultados: Foram localizados 68 artigos, e apos analise, 43 estudos, que abordavam os aspectos clinicos e/ou fisiopatologicos, foram selecionados. Discussao: A doenca de Werdnig-Hoffmann, atrofia muscular espinhal tipo I, e uma doenca hereditaria caracterizada pela atrofia e fraqueza muscular p