What is Progressive Bulbar Palsy?

Progressive bulbar palsy (PBP) is a form of motor neuron disease (MND). When people develop the condition, the neurons that communicate between the brain stem, spinal cord, and brain become damaged, causing symptoms like loss of speech and muscle twitching. PBP is considered a phenotype of amyotrophic lateral sclerosis (ALS).  

This article discusses the symptoms, causes, treatment, and prognosis for those diagnosed with the condition.

Progressive Bulbar Palsy Symptoms

The motor neurons affected by PBP are lower motor neurons. These cells send signals from upper motor neurons to the brain to control muscle movements. When PBP damages them, symptoms can include:

• Difficulty with swallowing due to pharyngeal muscle weakness
• Weak jaw and facial muscles
• Muscle twitching in the tongue and face
• Loss of speech that worsens over time
• Atrophy of the tongue
• Excessive drooling due to a lack of control over the mouth and facial muscles
• Limb weakness
• Emotional lability, which is abnormal crying or laughing fits
• Weight loss

People with PBP may be at an increased risk of choking. They also have a higher chance of developing a specific type of lung infection known as aspiration pneumonia, which occurs when food, liquids, and bacteria enter the lower airways and lungs. Those with the disorder are also more likely to develop a type of dementia known as frontotemporal dementia and cognitive impairment.

Causes

The exact cause of PBP is unknown. That said, genetics may play a role, and research has shown that people with PBP have a type of genetic expansion that affects the C9orf72 gene. The gene aids in making a protein that is found in neurons. Researchers are not yet clear on how this specific gene expansion plays a role in developing PBP.

The same gene has been correlated with the development of familial ALS, which is an inherited version of the disorder.

Diagnosis

Diagnosing PBP is based on several aspects of medical testing. Initially, health history and physical examination of symptoms will be done. After that, diagnostic tests will be performed to determine a definitive diagnosis. They include:

• Electrophysiological and neuroimaging tests: These tests are typically used to help rule out other conditions with similar symptoms.
• Nerve conduction studies: This test involves placing electrodes on the skin over the nerves suspected to be involved in the disease. The nerves are then stimulated with an electrical current. The electrical current provides data on how well the nerves are signalling.
• Needle electromyography: A needle-like electrode is placed into a muscle. The test measures electrical activity in the muscle to assess nerve signalling.

Treatment

There is no cure for PBP. Treatment can only make living with the disorder more comfortable. Therapies focus on alleviating symptoms and can include:

• Anticholinergic drugs or Botox to prevent or reduce drooling
• Gastrostomy, which is when a feeding tube is surgically placed into the stomach to ensure adequate nutrient intake
• Non-invasive and invasive ventilation, which involves the use of breathing aids to help a person who has difficulty breathing on their own
• Speech therapy to address any issues a person has with talking

Riluzole, which is a medication designed to slow down nerve cell damage, may also be given to slow the progression of the disease.

Prognosis

PBP is a fatal disease. Once a person is diagnosed, they will have to cope with it for the rest of their lives. Similar to ALS, people with PBP have a drastically reduced life expectancy. However, research shows that this specific phenotype is associated with a shorter survival time.

People diagnosed with the disease will have an average survival rate of six months to three years after their symptoms begin.  

Coping

Coping with a fatal disease is one of the hardest things a person will go through. However, there are ways they can support themselves through it. Some coping techniques to improve quality of life include:

• Joining a support group or leaning on friends and family for emotional support
• Establishing a strong medical care team
• Address any stressors you have head-on, such as financial stress, by reaching out to organizations that provide disability support
• Get well-acquainted with everything there is to know about the disease, so you have the knowledge necessary to manage it effectively

Summary

PBP is a phenotype of ALS that involves lower motor neuron damage, leading to excessive drooling, difficulty swallowing and talking, muscle twitching, and weakness in the face and tongue.

The exact cause of PBP isn’t well understood, but researchers believe genetics may play a role. Because medical scientists have yet to discover the source, there is no cure for the fatal disease. People diagnosed with PBP can undergo treatments using medications, feeding tubes, or breathing aids.

However, those therapies are designed to improve a person’s comfort and quality of life throughout their disease progression. People with PBP can expect to live anywhere from six months to three years after the onset of their symptoms. With a reduced life expectancy, focusing on the good things in life, such as family and loved ones, is essential.

A Word from Verywell

Receiving a PBP diagnosis can turn your entire life upside down. That said, it doesn’t have to destroy the time you have left. Give yourself time to grieve your situation and accept your fate.

That way, you can spend your remaining time with the people you love most, enjoy your life as much as possible, and be grateful for all the good moments you’ve experienced. It’s all easier said than done but staying positive is the best way to handle a fatal diagnosis.