My Clinical Notes

• Progressive degeneration of the upper and lower motor neurones in the spinal cord, cranial nerve nuclei and within the cortex
• Tends to start either as a problem in the bulbar muscles or as a problem with the limbs/trunk
• Bulbar weakness refers to weakness of the muscles supplied by CN IV, V and VII
• Mostly sporadic but there is a familial form associated with mutations in SOD
• Slight male preponderance
• Onset in middle life

 

Can be separated into 4 broad patterns;

 

Bulbar palsy

• LMN – muscles supplied by lower cranial nerves
• Weakness, wasting and fasciculations of the lower facial muscles and muscles moving the palate, pharynx, larynx and tongue

 

Pseudobulbar palsy

• UMN- weakness, slowness and spacticity of the muscles of the lower face, palate, larynx, pharynx and tongue
• Increased jaw jerk
• Emotional lability

 

• The clinical problems faced by these patients are;
  • Dysarthria
  • Dysphagia
  • Weight loss
  • Aspiration pneumonia
• These forms are more common in women

 

Progressive muscular atropy

• LMN affecting limbs and trunk
• Weakness, wasting and fasciculation
• Associated with frequent muscle cramps
• No sensory loss
• Muscles of the hand frequently involved

 

Amyotrophic lateral sclerosis

• UMN affecting limbs and trunk
• Weakness, spasticity, clonus and increased deep tendon reflexes
• Most commonly affects legs
• Sphincter control not affected
• No sensory loss

 

• As disease progresses there is a tendency for both UMN and LMN to be involved of both bulbar, trunk and limb muscles
• The involvement of respiratory and bulbar muscles make patients susceptible to chest infections

 

Diagnosis

• Largely clinical
• Confirmed by EMG and nerve conduction studies

 

Management

• Always progressive
• Death usually results from bronchopneumonia
• Riluzole is a sodium channel blocker which inhibits glutamate release, it slows progression and prolongs survival slightly
• Spacticity may be helped by baclofen
• Drooling can be aided by propantheline (antimuscarinic) or amytryptyline
• Ventilatory support
• Gastrostomy via PEG line

This entry was posted on Wednesday, October 24th, 2007 at 4:35 pm and is filed under Neurology. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.