Bulbar palsy and pseudobulbar palsy

Bulbar palsy is a lower motor neuron palsy that affects the nuclei of the IX^th, X^th, XI^th, and XII^th cranial nerves. Pseudobulbar palsy is an upper motor neuron palsy that affects the corticobulbar tracts of the V^th, VII^th, IX^th, X^th, XI^th, and XII^th cranial nerves. Any condition which disrupts or damages the cranial nerve nuclei or corticobulbar tracts can cause bulbar or pseudobulbar palsy (e.g., stroke, multiple sclerosis, infections, brain stem tumors). Both bulbar and pseudobulbar palsy are seen mainly in men over 75 years old and present with dysarthria and dysphagia. In addition, patients with pseudobulbar palsy present with a lack of facial expression, difficulty chewing, and emotional lability. Lower motor neuron signs (atrophy and fasciculations of the tongue, absent gag reflex) differentiate bulbar palsy from pseudobulbar palsy, which presents with upper motor neuron signs (spastic tongue, exaggerated gag, and jaw jerk reflexes). Diagnosis is mainly clinical. CSF analysis and MRI of the brain help identify the etiology. Treatment is mainly supportive.

• Age: 75–80 years
• Sex: ♂ > ♀

References:^[1][2]

Epidemiological data refers to the US, unless otherwise specified.

References:^{[3][4][4][5][6][7][8][9][10][11][12]}

Bulbar palsy and pseudobulbar palsy are clinical diagnoses based on clinical features. Tests are performed to diagnose the underlying condition.

• Investigations to diagnose the etiology
  • Serology for syphilis, poliomyelitis
  • CSF analysis for Guillain-Barré syndrome (albuminocytologic dissociation), multiple sclerosis (oligoclonal bands)
  • MRI brain for stroke, tumors, syringobulbia, multiple sclerosis

• No known treatment for irreversible causes of bulbar/pseudobulbar palsy
• Supportive therapy
  • Anticholinergics to control drooling
  • Baclofen for spasticity of pseudobulbar palsy
  • Percutaneous endoscopic gastrostomy tube (PEG): for patients with severe dysphagia or recurrent aspiration pneumonia
  • Speech and language therapy
  • Tricyclic antidepressants, SSRIs, or a combination of dextromethorphan hydrobromide and quinidine sulfate (Nuedexta): for patients with pseudobulbar affect
• Treat the underlying cause (see “Etiology” in table above)

References:^[13]