Читать книгу Spectrums of Amyotrophic Lateral Sclerosis - Группа авторов - Страница 13

ALS affects people of all ages, with a peak between ages 60 and 79. Recent population‐based studies reported a prevalence of ALS between 4.1 and 8.4 per 100 000 [7]. Patients with onset in the first two decades are extremely rare; such cases are termed juvenile ALS. This appears to be a different condition than classic ALS as it is familial in most cases, generally has autosomal recessive inheritance, and shows a very prolonged course. Patients with onset between 20 and 40 years are said to have young‐adult ALS; this is otherwise classic ALS, although it has peculiar clinical features including predominant UMN signs, male prevalence, and more prolonged survival (usually greater than five years). It remains unclear whether distinctive clinical features of young‐adult ALS are related to a different disease mechanism. Finally, very rare patients with onset before 20 years show an otherwise classic ALS with sporadic occurrence and an aggressive course. Most of the reported cases harbor a de novo mutation in the FUS gene.