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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.

	Bulbar palsy	Pseudobulbar palsy
Etiology	Brainstem stroke or tumors Neurodegenerative diseases: amyotrophic lateral sclerosis, syringobulbia Autoimmune neuropathies: Guillain-Barré syndrome, myasthenia gravis Infectious neuropathies: poliomyelitis, diphtheria, neurosyphilis	Stroke (multiple, recurrent strokes) Neurodegenerative disease: amyotrophic lateral sclerosis, progressive supranuclear palsy, multiple sclerosis Injury or malignancy of the high brainstem
Pathophysiology	Bilateral damage or injury of the nerve nuclei of cranial nerves IX, X, XI, and XII Lower motor neuron palsy of the respective muscles	Bilateral damage or injury of corticobulbar tracts to nerve nuclei of cranial nerves V, VII, IX, X, XI, and XII Upper motor neuron palsy of the respective muscles
Clinical features	Facial expression: normal Speech: nasal Dysphagia, drooling, nasal regurgitation Tongue Wasting Fasciculations Inability to protrude the tongue Palatal movement: absent Gag reflex: absent Jaw jerk: normal Emotions not affected	Facial expressions: absent (expressionless face) Speech: spastic dysarthria (husky, nasal voice) Difficulty in chewing Dysphagia, drooling, and nasal regurgitation Tongue Spastic, pointed Difficulty in tongue protrusion due to spasticity No wasting/ fasciculations Palatal movement: absent Gag reflex: brisk (exaggerated) Jaw jerk: exaggerated; clonic Pseudobulbar affect: emotional dysregulation with an affect that is out of proportion/incongruent with a situation (e.g., laughing hysterically after hearing devastating news)

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]