Amyotrophic Lateral Sclerosis Mimic Syndromes

Abstract

THE TERM amyotrophic lateral sclerosis (ALS) mimic syndrome has been used to describe a diverse group of conditions, the presentation and clinical features of which may resemble those of ALS at the outset. It has been estimated that up to 10% of patients initially diagnosed as having ALS are ultimately rediagnosed as having a disease other than ALS.^1,2 Thus, the correct diagnosis of ALS remains a complex clinical problem despite the increasing availability of improved diagnostic tests,³ the development of specific research criteria for diagnosis (the El Escorial criteria⁴), and a greater awareness among neurologists of the existence of ALS mimic syndromes.^5-7 With the exception of a similar study¹ of ALS mimic syndromes from Scotland, to our knowledge, there have been few published studies of ALS mimic syndromes and their importance in clinical practice.