In multiple sclerosis, slow conduction of motor and sensory pathways is due to.
This a chronic autoimmune inflammatory disease of CNS. It involves myelinated neurons. It destroys the myelin sheath as well as axons to varying degrees.
It has a varied course. Initial episodes are reversible neurological deficits. These later are followed by progressive neurological deficits.
Twice more common in females than males.
Affected age 20 tp 40 years.
About 50% of patients will need help walking within 15 years after the onset of the disease.
Four clinical types
1. Relapsing-remitting Multiple Sclerosis: the most common form, affecting about 85% of MS patients. It is marked by flare-ups (relapses or exacerbations) of symptoms followed by periods of remission when symptoms improve or disappear.
2. Secondary progressive Multiple Sclerosis: may develop in some patients with the relapsing-remitting disease. For many patients, treatment with disease-modifying agents helps delay such progression. The disease course continues to worsen with or without periods of remission or leveling off of symptom severity (plateaus).
3. Primary progressive Multiple Sclerosis: affects approximately 10% of MS patients. Symptoms continue to worsen gradually from the beginning. There are no relapses or remissions, but there may be occasional plateaus. This form of MS is more resistant to the drugs typically used to treat the disease.
4. Progressive-relapsing Multiple Sclerosis: a rare form, affecting fewer than 5% of patients. It is progressive from the start, with intermittent flare-ups of worsening symptoms along the way. There are no periods of remission.