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A diagnosis of Friedreich's ataxia requires a careful clinical examination, which includes a medical history and a thorough physical exam, in particular looking for balance difficulty, loss of proprioception, absence of reflexes, and signs of neurological problems. Genetic testing now provides a conclusive diagnosis. Other tests that may aid in the diagnosis or management of the disorder include:
- Electromyogram (EMG), which measures the electrical activity of muscle cells,
nerve conduction studies, which measure the speed with which nerves transmit impulses
- Electrocardiogram (ECG), which gives a graphic presentation of the electrical activity or beat pattern of the heart
- Echocardiogram, which records the position and motion of the heart muscle
- Blood tests to check for elevated glucose levels and vitamin E levels
- Magnetic resonance imaging (MRI) or computed tomography (CT) scans, tests which provide brain and spinal cord images that are useful for ruling out other neurological conditions
Clinical diagnosis is conducted on individuals with age onset between late teens and late forties who show the initial characteristics for the recessive autosomal cerebellar ataxia.
The following tests are performed:
- MRI brain screening for cerebellum atrophy.
- Molecular genetic testing for SYNE-1 sequence analysis.
- Electrophysiologic studies for polyneurotherapy
- Neurological examination
Prenatal diagnosis and preimplantation genetic diagnosis (PGD) can be performed to identify the mothers carrying the recessive genes for cerebellar ataxia.
Different types of ataxia:
- congenital ataxias (developmental disorders)
- ataxias with metabolic disorders
- ataxias with a DNA repair defect
- degenerative ataxias
- ataxia associated with other features.
Diagnosis of any cerebellar disorder or syndrome should be made by a qualified neurologist. Prior to referring a patient to a neurologist, a general practitioner or MS nurse will perform a finger-to-nose test. The clinician will raise a finger in front of the patient and ask him to touch it with his finger and then touch his nose with his forefinger several times. This shows a patient’s ability to judge the position of a target. Other tests that could be performed are similar in nature and include a heel to shin test in which proximal overshoot characterizes dysmetria and an inability to draw an imaginary circle with the arms or legs without any decomposition of movement. After a positive result in the finger-to-nose test, a neurologist will do a magnetic resonance image (MRI) to determine any damage to the cerebellum.
Cerebellar patients encounter difficulties to adapt to unexpected changes of the inertia of the limbs. This can be used to increase dysmetria and confirm a diagnosis of cerebellar dysfunction. Patients also show an abnormal response to changes in damping. These findings confirm a role of the cerebellum in predictions.
"For many years, it was thought that postural and balance disorders in cerebellar ataxia were not treatable. However, the results of several recent studies suggest that rehabilitation can relieve postural disorders in patients with cerebellar ataxia...There is now moderate level evidence that rehabilitation is efficient to improve postural capacities of patients with cerebellar ataxia – particularly in patients with degenerative ataxia or multiple sclerosis. Intensive rehabilitation programs with balance and coordination exercises are necessary. Although techniques such as virtual reality, biofeedback, treadmill exercises with supported bodyweight and torso weighting appear to be of value, their specific efficacy has to be further investigated. Drugs have only been studied in degenerative ataxia, and the level of evidence is low."
One approach is that it can be ameliorated to varying degrees by means of Frenkel exercises.
One main objective of the treatment is to re-establish the physiological inhibition exerted by the cerebellar cortex over cerebellar nuclei. Research using Transcranial direct-current stimulation (TCDCS) and Transcranial magnetic stimulation (TMS) shows promising results.
Additionally, mild to moderate cerebellar ataxia may be treatable with buspirone.
It is thought that the buspirone increases the serotonin levels in the cerebellum and so decreases ataxia.
In diagnosing autosomal dominant cerebellar ataxia the individuals clinical history or their past health examinations, a current physical examination to check for any physical abnormalities, and a genetic screening of the patients genes and the genealogy of the family are done. The large category of cerebellar ataxia is caused by a deterioration of neurons in the cerebellum, therefore magnetic resonance imaging (MRI) is used to detect any structural abnormality such as lesions which are the primary cause of the ataxia. Computed tomography (CT) scans can also be used to view neuronal deterioration, but the MRI provides a more accurate and detailed picture.
Individuals with cerebellar ataxia have full cognitive awareness: it is usually only the physical deterioration that prohibits them from participating in activities of daily living and any other relevant or desired interests. One of the most significant barriers in the lives of these individuals is dysarthria. Due to their cognitive stability, it is important that people who spend time with individuals with this disease are able to communicate as fully as possible with them. This is necessary in order to improve their day-to-day interactions.
Behavioral intervention is successful when it involves engaging knowledge of the interests and general backgrounds of individuals with cerebellar ataxia. Communication maximizing strategies are also useful, such as exaggeration of articulatory gestures, giving full attention to their responses, repeating where necessary, and slowing down speaking rate. Another intervention technique for speech is to focus on optimizing respiratory and vocal resources as well as training compensatory strategies.
These listed intervention techniques can improve quality of life in individuals with this disease and can be helpful for professionals/clinicians in the field as well as loved ones of those affected.
There is no known prevention of spinocerebellar ataxia. Those who are believed to be at risk can have genetic sequencing of known SCA loci performed to confirm inheritance of the disorder.
MJD can be diagnosed by recognizing the symptoms of the disease and by taking a family history. Physicians ask patients questions about the kind of symptoms relatives with the disease had, the progression and harshness of symptoms, and the ages of onset in family members.
Presymptomatic diagnosis of MJD can be made with a genetic test. The direct detection of the genetic mutation responsible for MJD has been available since 1995. Genetic testing looks at the number of CAG repeats within the coding region of the MJD/ATXN3 gene on chromosome 14. The test will show positive for MJD if this region contains 61-87 repeats, as opposed to the 12-44 repeats found in healthy individuals. A limitation to this test is that if the number of CAG repeats in an individual being tested falls between the healthy and pathogenic ranges (45-60 repeats), then the test cannot predict whether an individual will have MJD symptoms.
There is no known prevention of spinocerebellar ataxia. Those who are believed to be at risk can have genetic sequencing of known SCA loci performed to confirm inheritance of the disorder.
Physiotherapy intervention aims to improve balance and gait of OPCA patients, by stimulating neuroplastic changes in the atrophied neural structure. A challenge-oriented treatment program has previously been shown to be beneficial for individuals with ataxia from OPCA. The treatment program was composed of repetitive training with task challenges (e.g. obstacle course) and/or novel motor skills acquisition over a 12-week period under the supervision of a physiotherapist. Task challenges were progressed only when the patient showed mastery of a task.
Overground harness systems may be used to allow OPCA patients to challenge their balance without chance of falling. Furthermore, home exercise programs and/or aquatic exercises are used to allow more repetitions to facilitate balance learning. Treatment programs should be frequently monitored and adjusted based on a patient's progress. Outcome measures such as the Berg Balance Scale, Dynamic Gait Index and activities-specific balance confidence scales are useful to assess patient’s progress over time.
A person suffering from Friedreich's Ataxia may require some surgical interventions (mainly for the spine and heart). Often, titanium screws and rods are inserted in the spine to help prevent or slow the progression of scoliosis. As progression of ataxia occurs, assistive devices such as a cane, walker, or wheelchair are required for mobility and independence. Other assistive technology, such as a standing frame, can help reduce the secondary complications of prolonged use of a wheelchair. The goal of surgery is to keep the patient ambulatory as long as possible.
In many cases, patients experience significant heart conditions as well. These conditions are much more treatable, and are often countered with ACE inhibitors such as enalapril or lisinopril and other heart medications such as digoxin.
People with Friedreich’s ataxia may benefit from a conservative treatment approach for the management of symptoms. Health professionals educated in neurological conditions, such as physical therapists and occupational therapists, can prescribe an exercise program tailored to maximize function and independence. To address the ataxic gait pattern and loss of proprioception typically seen in persons with Friedreich’s ataxia, physical therapists can use visual cueing during gait training to help facilitate a more efficient gait pattern. The prescription of an assistive device along with gait training can also prolong independent ambulation.
Low intensity strengthening exercises should also be incorporated to maintain functional use of the upper and lower extremities. Fatigability should be monitored closely. Stabilization exercises of the trunk and low back can help with postural control and the management of scoliosis. This is especially indicative if the person is non-ambulatory and requires the use of a wheelchair. Balance and coordination training using visual feedback can also be incorporated into activities of daily living. Exercises should reflect functional tasks such as cooking, transfers and self-care. Along with gait training, balance and coordination training should be developed to help minimize the risk of falls.
Stretching exercises can be prescribed to help relieve tight musculature due to scoliosis and pes cavus deformities.
OPCA is characterized by progressive cerebellar ataxia, leading to clumsiness in body movements, veering from midline when walking, wide-based stance, and falls without signs of paralysis or weakness. Clinical presentation can vary greatly between patients, but mostly affects speech, balance and walking. Other possible neurological problems include spasmodic dysphonia, hypertonia, hyperreflexia, rigidity, dysarthria, dysphagia and neck dystonic posture.
There is no cure for spinocerebellar ataxia, which is currently considered to be a progressive and irreversible disease, although not all types cause equally severe disability.
In general, treatments are directed towards alleviating symptoms, not the disease itself. Many patients with hereditary or idiopathic forms of ataxia have other symptoms in addition to ataxia. Medications or other therapies might be appropriate for some of these symptoms, which could include tremor, stiffness, depression, spasticity, and sleep disorders, among others. Both onset of initial symptoms and duration of disease are variable. If the disease is caused by a polyglutamine trinucleotide repeat CAG expansion, a longer expansion may lead to an earlier onset and a more radical progression of clinical symptoms. Typically, a person afflicted with this disease will eventually be unable to perform daily tasks (ADLs). However, rehabilitation therapists can help patients to maximize their ability of self-care and delay deterioration to certain extent. Researchers are exploring multiple avenues for a cure including RNAi and the use of Stem Cells and several other avenues.
On January 18, 2017 BioBlast Pharma announced completion of Phase 2a clinical trials of their medication, Trehalose, in the treatment of SCA3. BioBlast has received FDA Fast Track status and Orphan Drug status for their treatment. The information provided by BioBlast in their research indicates that they hope this treatment may prove efficacious in other SCA treatments that have similar pathology related to PolyA and PolyQ diseases.
In addition, Dr. Beverly Davidson has been working on a methodology using RNAi technology to find a potential cure for over 2 decades. Her research began in the mid-1990s and progressed to work with mouse models about a decade later and most recently has moved to a study with non-human primates. The results from her most recent research "are supportive of clinical application of this gene therapy". Dr. Davidson along with Dr. Pedro Gonzalez-Alegre are currently working to move this technique into a Phase 1 clinical trial.
Finally, another gene transfer technology discovered in 2011 has also been shown by Dr. Davidson to hold great promise and offers yet another avenue to a potential future cure.
Physical therapists can assist patients in maintaining their level of independence through therapeutic exercise programmes. One recent research report demonstrated a gain of 2 SARA points (Scale for the Assessment and Rating of Ataxia) from physical therapy. In general, physical therapy emphasises postural balance and gait training for ataxia patients. General conditioning such as range-of-motion exercises and muscle strengthening would also be included in therapeutic exercise programmes. Research showed that spinocerebellar ataxia 2 (SCA2) patients with a mild stage of the disease gained significant improvement in static balance and neurological indices after six months of a physical therapy exercise training program. Occupational therapists may assist patients with incoordination or ataxia issues through the use of adaptive devices. Such devices may include a cane, crutches, walker, or wheelchair for those with impaired gait. Other devices are available to assist with writing, feeding, and self care if hand and arm coordination are impaired. A randomised clinical trial revealed that an intensive rehabilitation program with physical and occupational therapies for patients with degenerative cerebellar diseases can significantly improve functional gains in ataxia, gait, and activities of daily living. Some level of improvement was shown to be maintained 24 weeks post-treatment. Speech language pathologists may use both behavioral intervention strategies as well as augmentative and alternative communication devices to help patients with impaired speech.
Neuroimaging like MRI is important. However, there was considerable intrafamilial variability regarding neuroimaging, with some individuals showing normal MRI findings. Early individual prognosis of such autosomal recessive cerebellar ataxias is not possible from early developmental milestones, neurological signs, or neuroimaging.
There are five sub-types of MJD that are characterized by the age of onset and range of symptoms.
The sub-types illustrate a wide variety of symptoms that patients can experience. However, assigning individuals to a specific sub-type of the disease is of limited clinical significance.
- Type I is distinguished by arrival between the ages of 10 and 30 and represents approximately 13% of individuals. It usually has fast development and severe rigidity and dystonia.
- Type II is the most common sub-type (approximately 57% of individuals with MJD ) and typically begins between 20 and 50 years of age . It has an intermediate progression and causes symptoms that include spasticity, exaggerated reflex responses and spastic gait, ataxia and upper motor neuron signs.
- Type III MJD has a slow progression. Patients typically have an onset between the ages of 40 and 70 and represent approximately 30% of MJD patients. Symptoms include muscle twitching, tingling, cramps, unpleasant sensations such as numbness, pain in the feet, hands and limbs and muscle atrophy. Nearly all patients experience a decline in their vision such as blurred vision, double vision, inability to control eye movements, and loss of capability to distinguish color. Some patients also experience Parkinsonian symptoms.
- Type IV is distinguished by Parkinsonian symptoms that respond particularly well to levodopa treatment.
- Type V appears to resemble Hereditary Spastic Paraplegia; however, more research is needed to conclude the relationship between Type V MJD and hereditary spastic paraplegia.
Type 1 (AOA1) usually has an onset of symptoms during childhood. It is an autosomal recessive cerebellar ataxia (ARCA) associated with hypoalbuminemia and hypercholesterolemia. Mutations in the gene APTX, which encodes for aprataxin, have been identified to be responsible for AOA1. Elevated creatine kinase is occasionally present, in addition to a sensorimotor axonal neuropathy, as shown by nerve conduction velocity studies. In addition, MRI studies have shown cerebellar atrophy, mild brainstem atrophy, and, in advanced cases, cortical atrophy
There is currently no cure for SCA 6; however, there are supportive treatments that may be useful in managing symptoms.
Diagnosis consists of a variety of tests, including but not limited to:
- Measurement of orthostatic blood pressure
- Coordination
- rapid, alternating movements
- stroking of heel from along the opposite shin from knee to ankle
- finger-to-nose testing.
- Primary sensory modalities are examined with the following methods, searching for focal sensory loss, graded distal sensory loss, or levels of decreased sensation, hyperesthesia or dysesthesia.
- light touch
- pin-prick
- temperature
- position
- vibration
- Focused gait examination, which examines stationary position and walking abnormalities. Walking generally exposes any faults within the complex neurological communication between systems as weight is shifted from one foot to the other.
Treatment consists of physical rehabilitation programs designed to improve overall function, increase strength and improve balance. The ultimate goal is to increase the patient's degree of independence, thus improving the patient's quality of life. Exercise typically begins with simple movements, gradually transitioning into more complex actions. Various aspects of treatment are assessed based on the individual patient's condition, utilizing many assessment tools:
- Functional Reach Test
- External Perturbation Test – Push, Release
- External Perturbation Test – Pull
- Clinical Sensory Integration Test
- Single Leg Stance Test
- Five Times Sit to Stand Test
Various scales are also utilized
- Brief Ataxia Rating Scale
- Friedreich's Ataxia Impact Scale
- Scale For Assessment and Rating of Ataxia
Depending on subtype, many patients find that acetazolamide therapy is useful in preventing attacks. In some cases, persistent attacks result in tendon shortening, for which surgery is required.
In terms of a cure there is currently none available, however for the disease to manifest itself, it requires mutant gene expression. Manipulating the use of protein homoestasis regulators can be therapuetic agents, or a treatment to try and correct an altered function that makes up the pathology is one current idea put forth by Bushart, et al. There is some evidence that for SCA1 and two other polyQ disorders that the pathology can be reversed after the disease is underway. There is no effective treatments that could alter the progression of this disease, therefore care is given, like occupational and physical therapy for gait dysfunction and speech therapy.
Treatment of Ramsay Hunt Syndrome Type 1 is specific to individual symptoms. Myoclonus and seizures may be treated with drugs like valproate.
Some have described this condition as difficult to characterize.
FXTAS can be diagnosed using a combination of molecular, clinical, and radiological findings. In order for individuals to acquire FXTAS, they must first be permutation carriers, having between 55-200 CGG trinucleotide repeat expansion of the FMR1 gene. A definite, probable, or possible diagnosis of FXTAS can be assigned based on a clinician's confidence based on combined clinical or radiological findings in conjunction with the molecular permutation.
Clinical findings are divided into major and minor symptoms. Major symptoms include intention tremor and gait ataxia. Minor symptoms such as parkinsonism, short-term memory deficit, and executive function decline can further contribute to a diagnosis of FXTAS. Radiological findings are similarly divided into major and minor categories. As patients with FXTAS can have distinct brain scans from other movement disorders, a scan showing white matter lesions of the middle cerebellar peduncle is a major finding that can be attributed to FXTAS. Overall or generalized brain tissue atrophy and cerebral white matter lesions can also be minor indicators for a diagnosis.
For a definite diagnosis to be made, a major radiological finding and one major clinical finding must be present. Probable diagnosis can be made off either a major radiological finding and a minor clinical finding or two major clinical findings alone. The possible category for diagnosis can be made with a minor radiological finding and a major clinical finding.