What is the most common demyelinating disease of the CNS? explain its sign and symptoms? Give a factor that makes devoloping it less common? How is/was it diagnoised?
Most common demylinating disease is MS – which is a problem with attacks on the myelin in the CNS but not in the PNS. This is when the mylein sheath in CNS are destroyed leaving behind plaques (scars) which disrupt nervous functions.
There is more then one type of MS – some cause slower degeneration and other forms have a faster progression and the pt may grow worse quickly.
- MRI – can see plaques
Before the were MRI's doctors used to look for a weird collection of signs and symptoms – because the plaques would form randomly in the CNS causing random unrelated symptoms.
Symptoms of MS – MS symptoms come and go as the diseases moves in and out of remission (or relapse) slowly growing worse.
Ataxia – poor coordination (or poor motor control)
Eye issues – common in the early stages – such as blurred vission , due to optic nerve issues , or diplopia = double vision
Tingling in extremities (toes in fingers) , common early symptoms
Intention tremor – tremor in limbs when the person is intending to move
Fatigue – this can be very bad, during a flare up even putting on a heavy sweat shirt can can make a pt's arm to heavy to lift, another example would be sheets a pt in a flare up might not even be able to turn over with a sheet on them.
- Dysarthia – (you will find this and not aphasia in MS pt's) this is when there is a mechanical issue with producing speech. Pt's with this tend to speak in a very robotic manner. Example: broken jaw, or
- nerve issues with tongue.
(uncommon symptom) inappropriate laughter
Bowel and bladder issues – problems with voiding can lead to infections which can and often does kill the pt.
- Clinical Note: some patient find that it is sitting (hanging over a toilet) on a toilet which makes it hard to pee, so some pt may find they can only pee if they
- squat over a bucket.
- Lhermitte's sign, - sometimes called the Barber Chair phenomenon, is an electrical sensation that runs down the back and into the limbs. In many patients, it is elicited by bending the head forward. It can also be evoked when a practitioner pounds on the posterior
- cervical spine while the neck is flexed; this is caused by
- involvement of the posterior columns. Lhermitte's
- sign is named for Jacques Jean Lhermitte, a French neurologist and neuropsychiatrist. Thus it is incorrect to spell the term as "L'hermitte's sign". The sign suggests a lesion of the dorsal columns of the cervical cord or of the caudal medulla. Although often considered a classic finding in multiple sclerosis, it can be caused by a number of conditions, including transverse myelitis, Behçet's disease, trauma, radiation myelopathy, vitamin
- B12 deficiency (subacute combined degeneration), and compression of the spinal cord in the neck from any cause such as cervical spondylosis, disc herniation, tumor, and Arnold-Chiari malformation.
- This also happens in spinal menigitis.
There is no know cause or way to prevent MS. Also there is no animal model of MS which makes it hard to study. MS may be an autoimmune disease.
MS has 25% rate of concordance. Were as a disease like schisphenia has a 60% concordance rate.
Chances of developing MS if you live in a cold climate 50/100,000, the chance of contracting MS decreases if you grew up or at least spent up till your teen years in a warmer climate, this may have something to do with the thalamus but we don't really understand why this is yet. So the warmer the climate you were raised in the less chance of developing MS you have. Example: a pt who grew up in Denver has 10x greater chance of developing MS then a pt who grew up in new Orleans and 50x the chance of someone who grew up in new Mexico. Korea – has almost no cases of MS. When a pt develops MS heat is bad for them and may make there conditions worse, so cold is better for them.