Neuromuscular Junction Flashcards
What kind of disorder is Lambert Eaton?
Lambert Eaton Is a presynaptic neuromuscular junction disorder which demonstrates post exercise facilitation meaning at least 100% increase in first response or CMAP immediately following exercise.
OFTEN ASSOCIATED WITH AUTONOMIC SYMPTOMS SUCH AS DRY MOUTH
Where is the pathology in myasthenia gravis?
The postsynaptic neuromuscular junction Disorder.
Often associated with ptosis and extra ocular muscle weakness
Why does spasticity occur in ALS?
Involvement of the vestibulospinal and reticulospinal tracts
What is the median survival rate for ALS after diagnosis?
50% survival rate is 2.5 years after diagnosis.
Largely dependent on decision to use mechanical ventilation and/or feeding tube.
Five-year survival rate is between 4 to 30% and 10% will live for 10 years.
How does riuzole all work?
Anti-glutamate agent may be effective in slowing down the disease, prolonging ventilator time, and may improve survival in patients with bulbar onset disease.
However side effects can include asthenia and the medication is expensive
Describe SMA type 1 a.k.a. Werdnig- Hoffman disease.
- acute infantile onset SMA.
- severe disease often results in death by age 2-3 yrs.
- Disease onset is usually 3 to 6 months
- May never sit independently.
- rapid and fatal secondary to respiratory failure.
-SMA 2-3 have slower progression and later onset
What is kugelberg-Welanders disease?
SMA 3
- Lower motor neuron
- Onset typically between 2 and 15 years of age (later than type 1&2)
- typically normal life expectancy with slower progression than the other two variance.
- Patients usually achieve independent standing/walking.
- Kids usually have normal intelligence.
- Complications can include hand tremor, tongue fasciculations and areflexia.
What is chronic Werdnig- Hoffman?
SMA 2
- Disease onset is usually between two and 12 months and death (often by respiratory failure) occurs by 10 years of age.
- These patients can usually achieve milestones including independent sitting.
- They may be able to stand or walk with assistive devices.
What is the incidence of ALS?
1.6-2.4/100,000 population
What is the Halstead and Rossi criteria for a diagnosis of post polio syndrome?
- Confirmed history of poliomyelitis
- Partial to fairly complete neurologic and functional recovery.
- A period Of neurologic and functional stability of at least 15 years in duration.
- Onset of two or more of the following health problems since achieving a period of stability:
- unaccustomed 15
- muscle and or joint pain
- new weakness and muscles previously affected and or unaffected
- functional loss cold intolerance
- new atrophy - No other medical diagnosis to explain these health issues.
How does Mestinon (pyridostigmine) work?
Mestinon reversibly binds to and inactivates acetylcholinesterase, which is a cholinesterase inhibitor.
Other treatment options for myasthenia gravis including thymectomy, corticosteroids, immunosuppressive agents, and plasmapheresis
Which muscular dystrophy’s are known for cardiac involvement?
Beckers and Duchenne usually have an associate cardiomyopathy. cardiomyopathy may also be seen in a limb girdle muscular dystrophy. However it is not usually seen in fshd.
Describe facial scapulohumeral dystrophy.
Autosomal dominant
Dx childhood early adult
Proximal muscle weakness with facial muscle weakness. Popeye arm with cataracts inability to whistle. Unable to extend the wrist often with elbow contractions -protuberant scapula -Frontal balding -testicular atrophy -lordosis -pelvic girdle weakness Deafness -fundal changes -some patients may benefit from surgery that fixes the scapula to facilitate abduction of the arms
What is on the differential for a muscle biopsy showing type one fiber Atrophy?
Myotonic dystrophy, Nemaline red myopathy, fiber type disproportion
What is on the differential for muscle biopsy showing type 2 fiber atrophy?
Steroid myopathy, myasthenia gravis, deconditioning
