Motor Neuron Disease and Neuro-Muscular Junction Disorders Flashcards
What are the Motor Neuron Disease and Neuro-Muscular Junction Disorders talked about in this lecture?
Amyotrophic lateral sclerosis (ALS)
MYASTHENIA GRAVIS
LAMBERT-EATON MYASTHENIC SYNDROME (LEMS)
Botulism
What is the most common motor neuron diseases in adults?
ALS
Marked muscle atrophy ( amyotrophy ) and hardening of lateral spinal cord ( lateral sclerosis )
What are symptoms of ALS?
UMN + LMN signs and symptoms—spasticity and clumsiness with weakness and wasting
How many people get ALS?
1-2 per 100,000—- 5,000 new patients per year in USA
Most patients die within 3-5 years
What are most cases of ALS?
Most cases are sporadic but 5% are familial
What play a role in the cause of ALS?
Intraneuronal inclusions are characteristic
Excitotoxic injury to motor neurons from impaired removal of glutamate from synapses may play a role
Autoimmunity and environmental factors such as virus’ and toxins have also been hypothesized as a cause –together or alone
What upper and lower motor neuron clinical symptoms of ALS?
UMN signs– stiffness, spasticity, clumsiness, hyperactive reflexes, Babinski sign
LMN signs– weakness, wasting, fasciculations, decreased or absent reflexes
Preservation of EOM’s (extra ocular movements)
B/B function intact
No cognitive or sensory changes-???
What is symptomatic signs of ALS?
qsialorrhea,(drooling)
pseudo bulbar (emotional instability) affect,
muscle cramps,
spasticity,
dyspnea (labored breathing), depression, –use pharmaceuticals
Dysphagia (trouble swallowing)
What are treatments for the symptoms of ALS?
Respiratory care
Pseudobulbar affect—use dextromethorphan 20 mg and Quinidine 10 mg
Riluzole—block presynaptic release of glutamate
What is Myasthenia Gravis(MG)?
Autoimmune disorder with a postjunctional defect of Acetylcholine receptor ( AChR )
Most common in young women and older men
What are the Facial symptoms of MG?
Fluctuating weakness and fatigue in cranial , limb , or trunk muscles
50 % of initial symptoms involve the eye– ptosis, diplopia, blurred vision, 90 % eventually will have eye sx
What are symptoms of MG?
Facial weakness snarling appearance when laughing or trying to smile
Speech becomes increasingly slurred, nasal, or hoarse with talking; may lead to dysphagia, choking , or aspiration
May have profound weakness in neck muscles so props up head with hand
May get respiratory weakness and SOB
What is the most disabling symptom of MG?
Bulbar manifestations are often the most disabling symptoms
Which limbs are more affected in MG?
Arms are often more affected than the legs
Fatigue of muscles may increase throughout the day and worsen with sustained activity improving with rest
What are symptoms in pregnant pts?
In 1/3 of Myasthenic pts, pregnancy will worsen the condition in the 1st trimester.
In some pts, s/s improve during 2nd and 3rd trimesters coincident with relative immunosuppression during this phase of pregnancy
High risk returns after pregnancy
