What are the key clinical features to consider when diagnosing Amyotrophic Lateral Sclerosis (ALS) in a patient presenting with motor symptoms?

When diagnosing Amyotrophic Lateral Sclerosis (ALS) in a patient presenting with motor symptoms, key clinical features to consider include progressive muscular weakness that may initially present as isolated and unexplained symptoms such as loss of dexterity, frequent falls or trips, muscle wasting, twitching (fasciculations), cramps, stiffness, and bulbar symptoms like speech and swallowing difficulties or tongue fasciculations. Respiratory symptoms such as exertional shortness of breath or unexplained respiratory problems may also be early signs. Additionally, cognitive and behavioural changes, including emotional lability and frontotemporal dementia features, can be present in some cases. The diagnosis is primarily clinical, supported by the presence of both upper and lower motor neuron signs in multiple regions, with progressive spread of symptoms. Bulbar onset, characterized by speech and swallowing problems, is a significant presentation and is associated with a poorer prognosis. Early recognition of these features and prompt referral to a neurologist experienced in motor neurone disease is essential for diagnosis and management NICE NG42 Masrori & Van Damme 2020Quinn & Elman 2020Van Es 2024.