Hello and welcome to the Zero to Finals podcast. My name is Tom and in this episode I'm going

to be talking to you about multiple sclerosis. And you can find written notes on this topic at

zero to finals.com slash MS or in the neurology section of the zero to finals medicine book.

So let's get straight into it.

Multiple sclerosis, or MS, is defined as a chronic and progressive condition

that involves demyelination of the myelinated neurons in the central nervous system.

We'll talk in detail about the pathophysiology,

but basically this demyelination is thought to be caused by an inflammatory process

involving activation of immune cells against the myelin.

MS typically presents in young adults under the age of 50,

and it's more common in women.

Symptoms tend to improve in pregnancy and in the postpartum period. Let's talk about the path of physiology. Myelin is a material that covers

the axons of neurons in the central nervous system. The myelin helps the electrical impulses

to move faster along the axons. Remember, axons are sort of like cables within the central

nervous system that transmit messages between different neurons. And the myelin coats the axon and helps the signals

to move faster along it. Myelin is provided by cells that wrap themselves around the axons.

In the peripheral nervous system, the cells that provide myelin are called shorn cells, and in the central nervous

system, they're called oligodendrocytes. Multiple sclerosis typically only affects the central

nervous system and the oligodendrocytes. There is inflammation around the myelin and infiltration

of immune cells that cause damage to that

myelin. And this affects the way electrical signals travel along the nerve. And this leads to the

symptoms of multiple sclerosis. When patients present with symptoms of a clinical attack of multiple

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