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"What is the difference between ALS and MS?"

ZocdocAnswersWhat is the difference between ALS and MS?


My brother, who is 30 years old, was just diagnosed with ALS. Our mother had multiple sclerosis ? is that the same thing? Some of the symptoms seem similar.


ALS and MS are two different diseases. ALS, or amyotrophic lateral sclerosis (aka Lou Gehrig's Disease), affects upper and lower motor neurons. Damage to upper motor neurons (ie nerve cells arising in the brain), typically cause symptoms of stiffness, abnormal reflexes, and loss of fine motor skills. Damage to lower motor neurons (ie nerve cells arising in the spinal cord), typically cause muscles to weaken and atrophy, as well as twitch abnormally. By definition, it is a degenerative disease, which means that there is invariably a progression of symptoms over time, the rate of which may differ to some degree on an individual basis. MS, or multiple sclerosis, is an inflammatory disease that acts only within the central nervous system (ie the brain and spinal cord) and spares the peripheral nerves. Rather than destroying nerve cells themselves, MS causes symptoms by damaging the sheaths around the nerve cells (called myelin), leading to a reduction in the ability of the nerve cells to conduct electrical signals. Symptoms can vary greatly between individuals, ranging from visual disturbance to muscle weakness to difficulty with cognition. In general, there is greater variability in the course of progression of MS than ALS. With MS, most patients initially have discrete episodes of symptom attacks, between which they may see a complete remission of symptoms.

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