Pathophysiology- Neurologic Alterations Part 2

Multiple sclerosis

autoimmune destruction of myelin sheaths

What are some causes of multiple sclerosis?

some familial tendencies
viral disease (antibodies destroy myelin along nerve and impulse aren't getting transferred down the nerve like it should be)

What are the different types of multiple sclerosis?

relapsing-remitting
primary progressive
secondary progressive
progressive-relapsing

relapsing-remitting multiple sclerosis

exacerbations followed by partial or complete recovery/ remissions (most common)

primary progressive multiple sclerosis

slow but continuous neurologic decline
possible temporary plateaus

secondary progressive multiple sclerosis

starts as relapsing-remitting, then develops into steady neurologic decline

progressive-relapsing multiple sclerosis

progressive with exacerbations (most severe)

What are the clinical manifestations of multiple sclerosis?

diplopia (double vision)
random muscle weakness
fatigue
tingling of nerves
depression
changes in mood
dysphagia
dysarthria
ataxia
diarrhea or constipation
hypoesthesias
nystagmus
optic neuritis
unstable mood
spasms
incontinence
frequency or retention
para

Amyotrophic Lateral Sclerosis (ALS) (Lou Gerhig's Disease)

progressive degeneration of upper and lower motor neurons

What is the pathophysiology of ALS?

lower and upper motor degeneration and death--> demyelination and axonal scarring--> progressive muscle weakness

What are the clinical manifestations of ALS?

muscle twitching, cramping, stiffness
progressive muscle weakness and atrophy
flaccid (no tone) and spastic (stay contracted all the time) paralysis
respiratory failure
(Don't lose cognitive function)

What are some risk factors for ALS?

smoking
(possibly) lead and chemical exposure
glutamate exposure
tends to affect young adult to 40's
live only 3-5 yrs after diagnosis

Guillain-Barre Syndrome

Demyelinating disease of lower motor neurons (peripheral nervous system)

What are some triggers for Guillain-Barre Syndrome?

infection
injections (linked to flu vaccine)
surgery

What is the pathophysiology of Guillain-Barre Syndrome?

autoimmune destruction of myelin--> inflammation and aggregation of WBC--> segmental demyelination--> impaired nerve conduction

What are the clinical manifestations of Guillain-Barre Syndrome?

progressive ascending weakness (starts in feet and works its way up)
paresthesia (numbness and tingling)
neuropathic pain

Myasthenia Gravis

chronic autoimmune disease that affects the neuromuscular junction (point where the nerve is supposed to send message to muscle to contract)
thymic tumors or dysfunction
(increased risk of developing if already have an autoimmune disease)

What is the pathophysiology of Myasthenia Gravis?

autoantibodies (IgG) attack and bind to acetylcholine receptors
acetylcholine receptors are destroyed
acetylcholine is unable to bind
decreased transmission of nerve impulses across the neuromuscular junction
muscle unable to depolarize

What are the clinical manifestations of Myasthenia Gravis?

muscle fatigue (tire easily)
progressive weakness
affects eye, face, throat, mouth, neck first
diplopia (double vision)
ptosis (drooping of eyes)
occular palsies (twitching of eyes)
diaphragm and respiratory muscle weakness
facial drooping, expressionless

Myasthenic crisis

(where lack of acetylcholine is so severe)
severe muscle weakness
quadriplegia
respiratory insufficiency

Cholinergic crisis

result of acetylcholine toxicity
severe muscle weakness
quadriplegia
respiratory insufficiency
diarrhea
abdominal cramping
fasciculation
bradycardia
pupillary constriction
increased salivation
sweating

What are the diagnostic tests used for myasthenia gravis?

EMG
Antibody tests
Endrophonium chloride (Tensilon) test
Possible CT/ MRI to rule out thymoma

What are the types of degenerative joint diseases (DJD)?

degenerative disk disease (DDD)
spondyloisthesis (one disk slips out of line)
spinal stenosis (arthritis and inflammation causes spinal space to narrow)

What causes low back pain?

sprains, strains, tension, disc herniation, osteoporosis, hyperparathyroidism

What are the risks of low back pain?

occupation
obesity
smoking
osteoporosis

What are risks of a herniated disc?

trauma
DDD
incorrect lifting

What is the pathophysiology of a herniated disc?

tear in ligament and posterior capsule of the disk
nucleus pulposus leaks and increases pressure on nerve root
risk for spinal cord compression

What are the clinical manifestations of a herniated disc?

back pain
radiating pain (usually down a leg)
pain worse with movement, straight leg raise
decreased ROM
spinal tenderness
decreased sensation
diminished reflexes