Cerebellar Ataxia: Everything you need to know

We have all heard of neurological disorders like Alzheimer’s or Parkinson’s disease. Chances are, there is someone in your life with either diagnosis, as both are very common amongst the general population. Cerebellar ataxia, however, is not as prevalent. According to the National Ataxia Foundation, only 150,000 people in the United States have a form of the condition. But what exactly is cerebellar ataxia? What are the symptoms and its causes? Read further to learn everything you need to know about cerebellar ataxia.

What is Cerebellar Ataxia?

Ataxia is defined as a degenerative disease of the nervous system. It is hallmarked by a loss of full control over bodily movement. Thus, cerebellar ataxia describes a group of ataxias stemming from a part of the brain known as the cerebellum. The cerebellum is responsible for regulating muscular activity. Abnormal proteins hinder the function of nerve cells in cases of cerebellar ataxia. As cells in the cerebrum degenerate, symptoms progress.

Basic Symptoms of Cerebellar Ataxia

While there are various types of cerebellar ataxia to be discussed later, all types share some common symptoms. Symptoms of cerebellar ataxia consist of:

• Lack of coordination of the limbs, organs, or joints
• Unsteady gait with frequent stumbling; clumsiness
• Tremors
• Low muscle tone
• Fatigue
• Repetitive eye movements
• Dizziness
• Headaches
• Vocal changes
• Slurred speech
• Difficulty with fine motor skills such as walking, eating, etc.
• Cognitive and mood problems

Types of Cerebellar Ataxia

Cerebellar ataxia results from damage to the nervous system—specifically to the cerebellum and the spinal cord. Causes originating from dysfunction of the pathways to and from the cerebellum are also a possibility, as it interferes with the information sent to the brain.

There are three main types of cerebellar ataxia: acquired, hereditary, and idiopathic.

Acquired Cerebellar Ataxia

Symptoms of acquired cerebellar ataxia have a sudden, rapid onset. They are almost always caused by secondary events that precipitate brain damage.

Head Trauma

Cerebellar ataxia is not necessarily present at birth. Outside factors influence the condition. A car crash, sports accidents, or any trauma to the head causes sudden cerebellar ataxia symptoms.

Stroke

Cerebellar ataxia can transpire from stroke damage. A stroke is explained as damage to the brain that results from a blockage of its arteries. During this ischemic event, brain cells are compromised. Blood flow is prevented. The cells die off because the brain tissues do not have proper nutrients for functioning.

Infection

Chickenpox, Coxsackie disease, Epstein-Barr, and echovirus are viral infections that spread to the brain to cause cerebellar ataxia in rare cases.

Bacterial infections like meningitis and encephalitis manifest with brain inflammation, which ddamages brain cells and contribute to the many causes of cerebellar ataxia. Children are more prone than adults to developing cerebellar ataxia from an infection. Fortunately, ataxia caused from infection has a higher probability of healing with time.

Tumors or Cancer

Cancer and non-cancerous tumors are growths on the brain that damage the cerebellum. Tumors on other parts of the body can indirectly impair how the brain functions. Cerebellar ataxia is a secondary problem to the tumor or cancer.

Autoimmune Diseases

Autoimmune diseases are an immune response where the body attacks healthy cells. There are many autoimmune conditions, but multiple sclerosis, autoimmune thyroid disorders, and even celiac disease have a connection to cerebellar ataxia since they have the capability of damaging the nerve fibers that deliver signals to the brain and central nervous system.

Medication Side Effects

Certain medications produce toxic reactions that bring about cerebellar ataxia. Benzodiazepines, chemotherapy, and phenobarbital are a few drugs associated with toxic reactions.

Vitamin Deficiencies

Ataxia is a consequence of long-term vitamin deficiency. Vitamin E, vitamin b12, and thiamine are essential vitamins absorbed through diet. Gastrointestinal disorders, alcohol abuse, and other medical conditions impact their absorption. Supplementation to correct the deficiency usually improves the ataxia.

Hereditary Cerebellar Ataxia

Chronic cerebellar ataxias are frequently genetic—meaning the person is born with it and the condition runs in families. This might be displayed as a condition from birth such as cerebral palsy or in mitochondrial diseases and disorders. Professionals have determined genetic mutations that cause primary cerebellar ataxia, which are repeats “encoding a polyglutamine protein domain” (Fernandez, n.d.).

There are several types of genetic or hereditary cerebellar ataxias. Mutations causing cerebellar ataxia can be autosomal recessive where the afflicted patient has two copies of the gene or autosomal dominant where there is one faulty gene.

Friedreich’s Ataxia 

Friedreich’s ataxia is the most common type of hereditary ataxia. It is inherited by an autosomal recessive pattern. While incoordination and slurred speech follows the classic presentation of all ataxia conditions, Friedreich’s ataxia has a set of unique symptoms.

• Leg weakness requiring wheelchair use
• Difficulty swallowing (dysphasia)
• Diabetes
• Vision loss
• Curvature of the spine (scoliosis)
• Thickening of the heart (hypertrophic cardiomyopathy)
• Numbness and tingling/no sensation in hands and feet (neuropathy)
• Muscle wasting

Friedreich’s ataxia can develop in older adults, yet those in their mid 20s to 30s make the bulk of the patient population. The condition progresses over the course of years. Muscle wasting impacts walking first before it progresses to the feet, lower legs, and hands. Once leg weakness is prominent, wheelchair use is needed within 10 to 20 years. There is no cure.

Ataxia-telangiectasia

Although rare, Ataxia-telangiectasia is a childhood form of hereditary ataxia inherited by an autosomal recessive pattern. Aside from the basic ataxia symptoms, signs of Ataxia-telangiectasia include:

• Difficulty swallowing (dysphasia)
• Increased risk of cancer (leukemia or lymphoma)
• Slow eye movements
• Rapid head movements
• Clusters of blood vessels on face (telangiectasia)
• Immunocompromised—weakened immune system

Children with Ataxia-telangiectasia progress rapidly because the degeneration occurs in a variety of body systems. By age10, the majority of patients require a wheelchair to help with walking difficulties. Life span is decreased. Patients live until ages 19 to 25. The cause of death is frequently cancer related.

Wilson’s Disease Ataxia

Wilson’s disease is an autosomal recessive genetic condition that causes copper to accumulate in the brain and organs. Ataxia is a symptom which proceeds the accumulation of copper because the body is unable to remove the extra copper as it builds up. The progression of ataxia slows with early identification and treatment of the underlying disorder.

Congenital Ataxia

Whether congenital disorders like cerebral palsy or “secondary damage from neonatal hypoxic-ischemic encephalopathy or intrauterine strokes,” congenital ataxias are present at birth and are caused by damage to the cerebellum. (Fogel, 2012).  Subtle cases of congenital ataxia are overlooked, as the milder ataxia findings are assumed normal.

Spinocerebellar Ataxias

Spinocerebellar ataxias are a group of ataxias that begin in adulthood. Only in rare cases to children develop the condition. There are over 35 types of spinocerebellar ataxia, each with an autosomal dominant inheritance pattern. Signs and symptoms differ on the exact mutation, but the clumsiness from the lack of coordination is especially evident in spinocerebellar ataxia.

The following symptoms are persistent too:

• Memory loss with spoken language
• Muscle stiffness
• Muscle cramps
• Loss of sensation in hands and feet (peripheral neuropathy)
• Decreased bladder control (incontinence)

Lifespan is decreased as the symptoms progress.

Episodic Ataxia

Episodic ataxias are a group of autosomal dominant ataxia disorders that occur in episodes rather instead of rapidly progressing. The basic symptoms of ataxia wax and wane and patients with episodic ataxia have periods of reprieve when they are asymptomatic. With no progression, lifespan remains normal.

Additional symptoms of episodic ataxia are:

• Muscle spasms
• Vertigo
• Migraines
• Tinnitus
• Muscle twitching

Episodes of ataxia have triggers. Stress, fear of sudden movements, exercise, and caffeine or alcohol provokes symptoms that last from seconds to hours.

Sporadic Ataxias

Idiopathic late onset Cerebellar ataxias (ILOA) and Olivopontocerebellar atrophy are two terms used to define a group of progressive ataxia conditions with no identifiable cause. Changes in brain structure that produce its ataxia symptoms. No genetic mutation has been pinpointed at this time.

Onset of symptoms for sporadic ataxias is around 50 years of age. That is much later in life in comparison to other forms of cerebellar ataxia, but symptoms are no less severe. Nerves in the brain structures disappear as the condition progresses. Those with the diagnosis struggle with:

• Motor skills like walking
• Disturbed sleep
• Double vision
• Memory loss
• Bladder dysfunction
• Cognitive changes

A neurological condition called Multiple System Atrophy (MSA) regularly follows a diagnosis of sporadic ataxia. In MSA, ataxia is connected with an impairment of the autonomic nervous system. The autonomic nervous system controls all of the bodily functions that are supposed to occur automatically—heart rate, blood pressure, digestion, temperature regulation, sexual functions, bladder function, and more.

Diagnosing Cerebellar Ataxia

No single test exists to diagnose cerebellar ataxia. Instead, your doctor will use a wide range of diagnostic tools. Along with a checklist of neurological symptoms, doctors rely on a thorough family history and investigations by numerous specialists. However, a neurologist typically gives the overall diagnosis of the condition.

Imaging Studies

CT and/or MRI scans diagnose cerebellar ataxia by allowing your doctor to visualize detailed images of the brain and spinal cord. Lesions are a common finding in ataxia patients. Through contrast and non-contrast scans, your doctor can locate any cancerous tumors that directly or indirectly affect the cerebellum.

Nerve Studies

As previously mentioned, cerebellar ataxia leads to poor functioning nerve cells. A series of nerve conduction studies diagnose cerebellar ataxia by looking for neuropathy associated with the condition.

Electromyography (EMG)

An electromyogram is similar to the nerve conduction studies. The EMG records the electrical activity in the muscles, which is often diminished in cerebellar ataxia.

Spinal Tap

A spinal tap, or lumbar puncture, is a medical procedure that measures the cerebral spinal fluid. It is a useful diagnostic tool for diagnosing cerebellar ataxia because it tests for infection and inflammation of the cerebellum.

Genetic Testing

Genetic conditions are undoubtedly a cause for cerebellar ataxia. Exome sequencing pinpoints the exact genetic mutations. Mitochondrial DNA mutations, X-linked mutations, AD mutations, and POLG mutations are especially considered.

Miscellaneous

Multiple body systems suffer from a decrease in cerebellum nerve activity found in cerebellar ataxia. Specialists outside the field of neurology are needed to address its symptoms. For example, a gastroenterologist lends insight to cases of cerebellar ataxia through swallowing and GI motility studies. Pulmonology oversees lung function workups and a sleep study investigates breathing related issues.

Cerebellar Ataxia Treatment 

Treating cerebellar ataxia is much like its diagnosis progress. It requires a combination of treatment options to manage day-to-day symptoms. Remember, never implement new treatments before speaking with a trusted physician.

Medications

Depending on the original cause, medications do treat symptoms of cerebellar ataxia.

GABA Drugs: Gabapentin and Pregabalin

Gamma-amino butyric acid, or GABA, is a neurotransmitter that is reduced in cases of cerebellar ataxia. Gabapentin (Neurontin) is a seizure medication aiming to replenish GABA as it is depleted. Studies show that Gabapentin could have long-lasting effects that might prevent ataxia symptoms from worsening.

Pregabalin (Lyrica) is more potent that Gabapentin, but both are considered relatively safe. Side effects are few and include dizziness, fatigue, weight gain, cognition effects such as depression, and double vision. These side effects improve as the body adjusts to the medication.

Buspirone

Buspironeis an anti-anxiety medication. While ataxia is definitely not an anxiety disorder, Buspirone increases neurotransmitters—serotonin, dopamine, and norepinephrine that are reduced in cerebellar ataxia. Aspects of cerebellar function are enhanced by the drug. Its significance lies in the improvement in the accuracy of movement, as well as decreasing repetitive movements.

Improvements are seen within four weeks. Insomnia, dizziness, drowsiness, and headaches are mild side effects of Buspirone.

Tandospirone

Tandospirone acts similarly to other medications used to treat cerebellar ataxia, as it boosts neurotransmitters by promoting serotonin. The motor symptoms are not particularly responsive to the drug, but insomnia, depression, and pain are relieved by Tandospirone.

Side effects are not severe. They include a headache, gastrointestinal upset, dizziness, and fatigue.

Aminopyridine

Aminopyridine is a drug that modulates cerebellar activity. Vision changes and uncontrolled body movements are primary symptoms of ataxia and Aminopyridine regulates coordination as it pertains to eye movement with the rest of the body. Those with ataxia secondary to Multiple Sclerosis notice benefits since the drug is used to treat degenerative nerve conditions.

Side effects of Aminopyridine are seizures and cognitive impairments, which are not as mild as the side effects from alternative medication therapies.

Thyrotropin-Releasing Hormone

Thyrotropin-Releasing Hormone (TRH) is a hormone produced by the pituitary gland. TRH is labeled as a neurotransmitter when it goes to affect the nervous system. As it promotes blood flow to the cerebellum, ataxia symptoms lessen in severity. The Multiple System Atrophy Coalition states that TRH is not as effective for the type of cerebellar ataxia in Multiple System Atrophy. Side effects are few due to TRH naturally originating in the body.

Baclofen

Baclofen is a muscle relaxer commonly prescribed for patients with multiple sclerosis and spinal cord injury. Still, the drug treats cerebellar ataxia because it sensitizes the GABA receptors. Comparable to Aminopyridine, Baclofen improves eye coordination relating to body movement.

Users should take with caution because its side effects are seizures, hallucinations, impaired cognition, delayed reaction time, nausea, headaches, insomnia, and frequent urination.

Lifestyle Adjustments

Lifestyle changes come into play when the underlying cause of cerebellar ataxia is acquired by lifestyle factors. If exacerbated by a medication, like benzodiazepines, stopping the medication improves ataxia symptoms. If symptoms developed after a vitamin deficiency or alcohol abuse, a well-rounded diet and cutting out alcohol is imperative to treatment.

Additionally, all patients with cerebellar ataxia can benefit from a proper diet, as symptoms worsen when multiple influences are contributing to the condition like vitamin deficiencies.

Therapy for Cerebellar Ataxia

A variety of therapies are non-invasive treatment options for cerebellar ataxia.

Physical Therapy

Physical therapy is a therapy with a special focus on exercise. Those with cerebellar ataxia have muscle weakness caused by nerve cell death. However, a partial function can be restored or preserved through physical therapy centered around balance, gait, and muscle strengthening. Best long term outcomes require that the patient abide by the exercise plan for at least 8 to 12 weeks for rehabilitation. Exercises are closely monitored by a physical therapist and should be completed a minimum of 1 hour twice weekly.

Balance exercises like weight shifting with back and forth movements of arms or legs is key for increasing balance. Exercises such as sitting on an exercise ball while moving arms and legs or walking-heel-to toe with supervision can drastically help gait.

Occupational Therapy

The purpose of occupational therapy is to ensure patients are functioning optimally outside of the hospital. Chores, self-care, and hobbies—occupational therapists assist patients with daily tasks. Along with teaching strategies, occupational therapists perform a strict assessment to determine which interventions are necessary for the patient. Is the home accessible? Which tasks do they struggle with? How extensive is their muscle weakness? After answering those important questions, patients receive modified utensils for motor tasks (i.e. eating), computer technology to facilitate communication and speaking, plus walkers, wheelchairs, or canes to support walking.

Speech Therapy

Trouble swallowing, which is known as dysphagia, is a symptom of cerebellar ataxia. A lack of muscle coordination inhibits the swallowing mechanism for food, water, and saliva secretions. In cerebellar ataxia, dysphagia is accompanied by a motor speech disorder called dysarthria. Symptoms that cause problems with communication are altered voice quality, slurred speech, and intelligibility. Cognitive impairment and ear/ hearing involvement also contribute.

Speech therapy is an intervention to enhance a patient’s communication. Exercises to strengthen the throat muscles are the first step in speech therapy. Therapists have patients over-articulate, use shorter phrases, and apply breathing techniques while talking. For trouble swallowing, speech therapists work side-by-side with occupational therapists to manage dysphagia by offering advice on oral hygiene, modifying diet, demonstrating appropriate eating positions, and monitoring when to implement tube feeding medical interventions.

Each specialist in the patient’s care has the same goal in mind, and that is to improve life with cerebellar ataxia.

References

Fernandez, Hubert. “Ataxia.” Chorea & Huntington’s Disease, International Parkinson and Movement Disorder Society, www.movementdisorders.org/MDS/About/Movement-Disorder-Overviews/Ataxia.htm.

Fogel, B. L. (2012).Childhood cerebellar ataxia. Journal of child neurology, 27(9),1138-45.

Matsugi, A. (2017). Physical Therapy for Cerebellar Ataxia, DOI: 10.5772/67649