Progressive bulbar palsy

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Progressive bulbar palsy
Specialty Neurology

Progressive bulbar palsy (PBP) is a medical condition. It belongs to a group of disorders known as motor neuron diseases. [1] PBP is a disease that attacks the nerves supplying the bulbar muscles. These disorders are characterized by the degeneration of motor neurons in the cerebral cortex, spinal cord, brain stem, and pyramidal tracts. This specifically involves the glossopharyngeal nerve (IX), vagus nerve (X), and hypoglossal nerve (XII). [2]

Contents

This disorder should not be confused with pseudobulbar palsy or progressive spinal muscular atrophy. [2] The term infantile progressive bulbar palsy is used to describe progressive bulbar palsy in children. The ICD-11 lists progressive bulbar palsy as a variant of amyotrophic lateral sclerosis (ALS). [3]

Signs and symptoms

Prognosis for PBP patients is poor. Progressive bulbar palsy symptoms can include progressive difficulty with talking and swallowing. [4] Patients can also exhibit reduced gag reflexes, weak palatal movements, fasciculations, and weak movement of the facial muscles and tongue. In advanced cases of PBP, patients may be unable to protrude their tongue or manipulate food in their mouth. [5]

Patients with early cases of PBP have difficulty with pronunciations, particularly lateral consonants (linguals) and velars, and may show problems with drooling saliva. If the corticobulbar tract is affected a pseudobulbar affect with emotional changes may occur. [4] Because PBP patients have such difficulty swallowing, food and saliva can be inhaled into the lungs. This can cause gagging and choking, and it increases the risk of pneumonia. [4] Death, which is often from pneumonia, usually occurs one to three years after the start of the disorder.[ citation needed ]

About twenty-five percent of patients with PBP eventually develop the widespread symptoms common to ALS. [6]

Cause

The cause of PBP is unknown. One form of PBP is found to occur within patients that have a CuZn-superoxide dismutase (SOD1) mutation. [7] Progressive bulbar palsy patients that have this mutation are classified with FALS patients, Familial ALS (FALS) accounts for about 5%-10% of all ALS cases and is caused by genetic factors. Within these, about 20–25% are linked to the SOD1 mutation. It is not currently known if and how the decreased SOD1 activity contributes to Progressive Bulbar Palsy or FALS, and studies are being done in patients and transgenic mice to help further understand the impact of this gene on the disease.[ citation needed ]

A case study was done on a 42-year-old woman who complained of muscle weakness 10 months prior to admission in the hospital. Upon neurological examination, the patient showed muscle atrophy, fasciculation in all limbs and decreased deep tendon reflexes. The patient's older brother, father, and paternal uncle had previously all died of ALS or an ALS type syndrome. The patient developed progressive bulbar palsy, became dependent on a respirator, and had two episodes of cardiac arrest. The patient died from pneumonia two years after the onset of the disease. After studying the patient, it was found that the patient had a two base pair deletion in the 126th codon in exon 5 of the SOD1 gene. This mutation produced a frameshift mutation, which led to a stop codon at position 131. SOD1 activity was decreased by about 30%. The patient's histological examination showed severe reduction in lower motor neurons. Upon further study, this case proved to be important because it demonstrated that SOD1 mutations might not effect steady neuropathological changes, and that environmental and genetic factors might affect the phenotype of the SOD1 mutations. [7]

Treatment

PBP is aggressive and relentless, and there were no treatments for the disease as of 2005. [4] However, early detection of PBP is the optimal scenario in which doctors can map out a plan for management of the disease. This typically involves symptomatic treatments that are frequently used in many lower motor disorders.[ citation needed ]

History

The disease was first recognized by the French neurologist Guillaume Duchenne in 1860 and termed, "labioglossolaryngeal paralysis". [8] In 1859, Wachsmuth changed the name to progressive bulbar palsy. In 1869, Charcot studied the involvement of the corticospinal tracts and with Joffroy, who noted the loss of the bulbar motor nuclei, discovered the similarities to amyotrophic lateral sclerosis (ALS). [8] It was observed that a distinction from ALS was fatigue that predominated in muscles innervated by lower cranial nerve nuclei, rather than the upper motor neurons.[ citation needed ]

See also

Related Research Articles

<span class="mw-page-title-main">Motor neuron diseases</span> Group of neurological disorders affecting motor neurons

Motor neuron diseases or motor neurone diseases (MNDs) are a group of rare neurodegenerative disorders that selectively affect motor neurons, the cells which control voluntary muscles of the body. They include amyotrophic lateral sclerosis (ALS), progressive bulbar palsy (PBP), pseudobulbar palsy, progressive muscular atrophy (PMA), primary lateral sclerosis (PLS), spinal muscular atrophy (SMA) and monomelic amyotrophy (MMA), as well as some rarer variants resembling ALS.

Neuromyotonia (NMT) is a form of peripheral nerve hyperexcitability that causes spontaneous muscular activity resulting from repetitive motor unit action potentials of peripheral origin. NMT along with Morvan's syndrome are the most severe types in the Peripheral Nerve Hyperexciteability spectrum. Example of two more common and less severe syndromes in the spectrum are Cramp Fasciculation Syndrome and Benign Fasciculation Syndrome. NMT can have both hereditary and acquired forms. The prevalence of NMT is unknown.

<span class="mw-page-title-main">Benign fasciculation syndrome</span> Medical condition

Benign fasciculation syndrome (BFS) is characterized by fasciculation (twitching) of voluntary muscles in the body. The twitching can occur in any voluntary muscle group but is most common in the eyelids, arms, hands, fingers, legs, and feet. The tongue can also be affected. The twitching may be occasional to continuous. BFS must be distinguished from other conditions that include muscle twitches.

<span class="mw-page-title-main">Fasciculation</span> Spontaneous, involuntary muscle twitch

A fasciculation, or muscle twitch, is a spontaneous, involuntary muscle contraction and relaxation, involving fine muscle fibers. They are common, with as many as 70% of people experiencing them. They can be benign, or associated with more serious conditions. When no cause or pathology is identified, they are diagnosed as benign fasciculation syndrome.

Lower motor neurons (LMNs) are motor neurons located in either the anterior grey column, anterior nerve roots or the cranial nerve nuclei of the brainstem and cranial nerves with motor function. Many voluntary movements rely on spinal lower motor neurons, which innervate skeletal muscle fibers and act as a link between upper motor neurons and muscles. Cranial nerve lower motor neurons also control some voluntary movements of the eyes, face and tongue, and contribute to chewing, swallowing and vocalization. Damage to the lower motor neurons can lead to flaccid paralysis, absent deep tendon reflexes and muscle atrophy.

Primary lateral sclerosis (PLS) is a very rare neuromuscular disease characterized by progressive muscle weakness in the voluntary muscles. PLS belongs to a group of disorders known as motor neuron diseases. Motor neuron diseases develop when the nerve cells that control voluntary muscle movement degenerate and die, causing weakness in the muscles they control.

<span class="mw-page-title-main">Progressive muscular atrophy</span> Medical condition

Progressive muscular atrophy (PMA), also called Duchenne–Aran disease and Duchenne–Aran muscular atrophy, is a disorder characterised by the degeneration of lower motor neurons, resulting in generalised, progressive loss of muscle function.

<span class="mw-page-title-main">Fazio–Londe disease</span> Medical condition

Fazio–Londe disease (FLD), also called progressive bulbar palsy of childhood, is a very rare inherited motor neuron disease of children and young adults and is characterized by progressive paralysis of muscles innervated by cranial nerves. FLD, along with Brown–Vialetto–Van Laere syndrome (BVVL), are the two forms of infantile progressive bulbar palsy, a type of progressive bulbar palsy in children.

Pseudobulbar palsy is a medical condition characterized by the inability to control facial movements and caused by a variety of neurological disorders. Patients experience difficulty chewing and swallowing, have increased reflexes and spasticity in tongue and the bulbar region, and demonstrate slurred speech, sometimes also demonstrating uncontrolled emotional outbursts.

Bulbar palsy refers to a range of different signs and symptoms linked to impairment of function of the glossopharyngeal nerve, the vagus nerve, the accessory nerve, and the hypoglossal nerve. It is caused by a lower motor neuron lesion in the medulla oblongata, or from lesions to these nerves outside the brainstem, and also botulism. This may be caused by any of a number of genetic, vascular, degenerative, inflammatory, and other underlying conditions. It can be differentiated from pseudobulbar palsy. When there is airway obstruction, intubation is used.

<span class="mw-page-title-main">Canine degenerative myelopathy</span>

Canine degenerative myelopathy, also known as chronic degenerative radiculomyelopathy, is an incurable, progressive disease of the canine spinal cord that is similar in many ways to amyotrophic lateral sclerosis (ALS). Onset is typically after the age of 7 years and it is seen most frequently in the German shepherd dog, Pembroke Welsh corgi, and boxer dog, though the disorder is strongly associated with a gene mutation in SOD1 that has been found in 43 breeds as of 2008, including the wire fox terrier, Chesapeake Bay retriever, Rhodesian ridgeback, and Cardigan Welsh corgi. Progressive weakness and incoordination of the rear limbs are often the first signs seen in affected dogs, with progression over time to complete paralysis. Myelin is an insulating sheath around neurons in the spinal cord. One proposed cause of degenerative myelopathy is that the immune system attacks this sheath, breaking it down. This results in a loss of communication between nerves in lower body of the animal and the brain.

<span class="mw-page-title-main">SOD1</span> Protein-coding gene in the species Homo sapiens

Superoxide dismutase [Cu-Zn] also known as superoxide dismutase 1 or hSod1 is an enzyme that in humans is encoded by the SOD1 gene, located on chromosome 21. SOD1 is one of three human superoxide dismutases. It is implicated in apoptosis, familial amyotrophic lateral sclerosis and Parkinson's disease.

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<span class="mw-page-title-main">Monomelic amyotrophy</span> Medical condition

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References

  1. Lapiedra 2002
  2. 1 2 Hughes 1998
  3. "ICD-11 - Mortality and Morbidity Statistics". icd.who.int. Retrieved 22 October 2020.
  4. 1 2 3 4 Merck 2005
  5. Campbell 2005
  6. Swash 2000
  7. 1 2 Kadekawa 1997
  8. 1 2 Fawcett 2000

Bibliography