ALS [Guest Lecture} Flashcards
Describe ALS
ALS is a family of disorders affects upper and/or lower motor neurons
It can be inheritied or sporadics
All forms are progressive and spare sensory neurons
Includes: ALS, PMa, PLS, PBP (IBALS), and SMA
List the areas of the nervous system affected by ALS
BOTH UMN and LMN
- Motor cortex
- Corticospinal/bulbar stracts
- Brainstem
- Anterior horn spinal neurons
List the sx of ALS
- Weakness: hands, arms, leg, mm of speech/swallowing/breathing
- Mm fasciculation and cramping
- Dysarthria and dysphagia
- Respiratory compromise
Differentiate between UMN and LMN signs
UMN = spasticity, hyperreflexia, pseudobulbar sx
LMN = weakness, atrophy, fasciculation
List the negative sx (rule out) for ALS
- Lack of progression
- Sensory impairment
- Visual decline
- B/B dysfunction
- Imaging, EMG, or other evidence of alternative disease
List the DDx for ALS
- HIV
- Lyme disease
- Syphilis
- MS
- Post-polio syndrome
- Spinal mm atrophy
- Kennedy’s disease
Describe the pathophysiology of Sporadic ALS (sALS)
No linked to any specific factors
Pathophysiology is complex, likely interaction of multiple environmental and genetic factors
Describe the pathophysiology of familial ALS (fALS)
Autosomal dominant, mutation in superoxide dismutase type 1 (SOD1), TDP41, ubiquitin-2, and/or C9ORF72 genes
5-10% of ALS cases
Describe the cellular cascade of ALS
Once intiated…
Oxidative stress > glutamate induced excitotoxicity > intracellular protein aggration > mitochondiral dysfunction > growth factor deficiency > axonal transport failure > capsase enzyme activity
Condition:
- LMN degeneration with UMN sparing
- Onset 40-60
- Often converts to ALS
- 5 year survival rate of 33%
Progressive Muscular Atrophy
Condition:
- UMN degeneration with LMN sparing
- Onset 40-60 yo
- Clinical course over 2-3 yrs confirms dx
- May convert to ALS
- NOT considered fatal
- 16 year survival rate 77%
Primary Lateral Sclerosis
Condition:
- Degerenation of lower CN (IX, X, XI, XII)
- Rarely occurs w/o some involvement of extremities
- Pseudobulblar affect
- Frontotemporal dementia
Progressive bulbar palsy
Condition:
- Family of hereditary MN disorders
- Infantile onset
- 2 year lifespan
Spinal Muscular Atrophy
Type 1 or Werdnig-Hoffman
Condition:
- Family of hereditary MN disorders
- Onset 6-18 mo
- Survive into adulthood
- Significant motor impairment
Spinal Muscular Atrophy
Type 2 or Juvenile/Chronic
Condition
- Family of hereditary MN disorders
- Onset in toddlerhood/adolescence
- Usually remain ambulatory
- Increased risk for respiratory compromise
Spinal Muscular Atrophy
Type 3 or Wolhlfart-Kugelberg-Welander
