ALS Mimics

AbstractAmyotrophic lateral sclerosis (ALS) is a fatal neurodegenerative disease. Most patients die within 2–5 years of symptom onset due to the lack of effective therapy options. A diagnostic delay is encountered quite often, since disease progression as well as site and speed of onset may vary significantly. Some diseases can mimic features of ALS, especially in early stages. It is very important to differentiate those mimics from ALS as potentially treatable conditions might be missed otherwise. ALS typically affects the upper as well as the lower motor neuron, which implies that diseases sharing at least one of these clinical features have to be considered in the differential diagnosis. The following conditions should be taken into account as a differential diagnosis for ALS with predominant affection of the lower motor neuron: Immune mediated neuropathies such as multifocal motor neuropathy (MMN) with pronounced distal paresis without striking atrophy signs and conduction blocks in electroneurography, and chronic inflammatory demyelinating polyradiculoneuropathy (CIDP) with common signs of sensibility disturbances, areflexia and cytoalbuminologic dissociation in the cerebrospi