ALS

| image = ALS Affected neurons and muscles.png | caption = Parts of the nervous system affected by ALS, causing progressive symptoms in skeletal muscles throughout the body | field = Neurology | symptoms = Early: Stiff muscles, muscle twitches, gradual increasing weakness
Later: Difficulty in speaking, swallowing, and breathing; respiratory failure; 10–15% experience frontotemporal dementia | complications = Falling (accident); Respiratory failure; Pneumonia; Malnutrition | onset = 45–75 years | duration = | causes = Unknown (about 85%), genetic (about 15%) | risks = Genetic risk factors; age; male sex; heavy metals; organic chemicals; smoking; electric shock; physical exercise; head injury | diagnosis = Clinical diagnosis of exclusion based on progressive symptoms of upper and lower motor neuron degeneration in which no other explanation can be found. Supportive evidence from electromyography, genetic testing, and neuroimaging | differential = Multifocal motor neuropathy, Kennedy's disease, Hereditary spastic paraplegia, Nerve compression syndrome, Diabetic neuropathy, Post-polio syndrome, Myasthenia gravis, Multiple sclerosis | prevention = | treatment = Walker (mobility); Wheelchair; Non-invasive ventilation; Feeding tube; Augmentative and alternative communication; symptomatic management | medication = Riluzole, Edaravone, Sodium phenylbutyrate/ursodoxicoltaurine, Tofersen, Dextromethorphan/quinidine | prognosis = Life expectancy highly variable but typically 2–4 years after diagnosis | frequency = }} | deaths = | alt = Diagram of a human nervous system highlighting the brain, spinal cord, motor neurons, and muscles of the body affected by ALS }}

Amyotrophic lateral sclerosis (ALS), also known as motor neurone disease (MND) or '''Lou Gehrig's disease (LGD''') in the United States, is a rare, terminal neurodegenerative disorder that results in the progressive loss of both upper and lower motor neurons that normally control voluntary muscle contraction. ALS is the most common form of the motor neuron diseases. ALS often presents in its early stages with gradual muscle stiffness, twitches, weakness, and wasting. Motor neuron loss typically continues until the abilities to eat, speak, move, and, lastly, breathe are all lost. While only 15% of people with ALS also fully develop frontotemporal dementia, an estimated 50% face at least some minor difficulties with thinking and behavior. Depending on which of the aforementioned symptoms develops first, ALS is classified as ''limb-onset'' (begins with weakness in the arms or legs) or ''bulbar-onset'' (begins with difficulty in speaking or swallowing).

Most cases of ALS (about 90–95%) have no known cause, and are known as ''sporadic ALS''. However, both genetic and environmental factors are believed to be involved. The remaining 5–10% of cases have a genetic cause, often linked to a family history of the disease, and these are known as ''familial ALS'' (hereditary). About half of these genetic cases are due to disease-causing variants in one of four specific genes. The diagnosis is based on a person's signs and symptoms, with testing conducted to rule out other potential causes.

There is no known cure for ALS. The goal of treatment is to slow the disease progression, and improve symptoms. FDA approved treatments that slow the progression of ALS include riluzole and edaravone. Non-invasive ventilation may result in both improved quality, and length of life. Mechanical ventilation can prolong survival but does not stop disease progression. A feeding tube may help maintain weight and nutrition. Death is usually caused by respiratory failure. The disease can affect people of any age, but usually starts around the age of 60. The average survival from onset to death is two to four years, though this can vary, and about 10% of those affected survive longer than ten years.

Descriptions of the disease date back to at least 1824 by Charles Bell. In 1869, the connection between the symptoms and the underlying neurological problems was first described by French neurologist Jean-Martin Charcot, who in 1874 began using the term ''amyotrophic lateral sclerosis''. Provided by Wikipedia