Both amyotrophic lateral sclerosis, also known as Lou Gehrig's Disease, and multiple sclerosis are neurological diseases that impair the full functionality of the central nervous system by attacking nerve and muscle function. They share some similarities in how they affect the body, and differentiating between the two is critical for pursuing the correct treatment path. Understanding the differences helps patients seek the most appropriate doctors and medications.
Symmetry of Symptoms
The Center for Neurologic Study notes that symmetry is a means to differentiate between symptoms of ALS and MS. Multiple sclerosis primarily affects one side of the body, while ALS affects the whole body. The National Institute of Neurological Disorders and Stroke notes that although ALS symptoms may initially start on one side or the other, it is muscle atrophy and nerve damage on both sides that separates ALS from other forms of sclerosis and muscular dystrophy.
Demyelination refers to the damage to the myelin sheath that covers nerves in the body. For patients with MS, damage to the myelin sheath is a primary symptom of the disease, according to the National MS Society, as this damage causes the scar tissue that disrupts the nerve pulse communication. The Center for Neurologic Study reports that patients with ALS do not show demyelination as a primary nerve symptom. Instead, for ALS patients, demyelination will be a secondary symptom arriving after muscle atrophy sets in.
According to the Center for Neurologic Study, a key difference between ALS and MS is the presence of inflammation around the nerve pathways. In patients with multiple sclerosis, inflammatory cells surround areas where the myelin sheath has been damaged, and this inflammatory cell presence is a key diagnostic for the disease. Individuals with Lou Gehrig's disease, on the other hand, show no signs of inflammatory cells around their nerves in medical tests. Although patients may not be able to see this symptom, it is a beacon for doctors seeking to make an accurate prognosis.
The ALS Association notes that the disease is rapidly progressive and fatal, with most patients having just a three- to five-year life expectancy. The National Multiple Sclerosis Society notes that symptoms of MS may come and go and that while symptoms may worsen with time, they can be controlled with medications, resulting in a full life expectancy.