ALS is the unifying term for this heterogeneous syndrome and time to question the dogma forged at El Escorial

Historically characterised as a neuromuscular disease involving progressive loss of both central and peripheral motor neurons, amyotrophic lateral sclerosis (ALS) now sits among the cerebral neurodegenerative syndromes, involving clinical, pathological and genetic overlap with frontotemporal dementia (FTD). Descriptions of progressive lower motor neuron degeneration and associated muscle wasting, termed progressive muscular atrophy (PMA), were published by anatomists such as Charles Bell as early as 1836. Jean-Martin Charcot’s later contribution was the unique clinicopathological linking of the upper and lower motor neuron degeneration, which he termed ALS, since when PMA has become associated with a lower motor neuron-only variant. Wilhelm Erb and Pierre Marie are associated with identifying the upper motor neuron-only variant of progressive weakness, termed primary lateral sclerosis (PLS). In their JNNP paper, de Vries and colleagues1 demonstrate that so-called PMA and PLS cases show cognitive and behavioural impairment within the spectrum inherent to more typical ALS. In doing this so definitively, with large well-characterised groups, they add to a body of evidence that should call time on the confusing lexicon of phenotypic terms that frequents the penumbra of ALS.

‘What type of ALS do I have?’ This common question in the clinic reflects public awareness of variation in the clinical presentation and …