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ARSACS is usually diagnosed in early childhood, approximately 12–24 months of age when a child begins to take their first steps. At this time it manifests as a lack of coordination and balance resulting in frequent falls. Some of the signs and symptoms include:
- Stiffness of the legs
- Appendicular and trunk ataxia
- Hollow foot and hand deformities
- Ataxic dysarthria
- Distal muscle wasting
- Horizontal gaze nystagmus
- Spasticity
Most patients begin to use a wheelchair for movement around age 30-40. Death usually occurs in their 60s, but some have been reported to live longer.
Autosomal recessive cerebellar ataxia type 1 (ARCA1) is a condition characterized by progressive problems with movement. Signs and symptoms of the disorder first appear in early to mid-adulthood. People with this condition initially experience impaired speech (dysarthria), problems with coordination and balance (ataxia), or both. They may also have difficulty with movements that involve judging distance or scale (dysmetria). Other features of ARCA1 include abnormal eye movements (nystagmus) and problems following the movements of objects with their eyes. The movement problems are slowly progressive, often resulting in the need for a cane, walker, or wheelchair.
Symptoms typically are onset in the adult years, although, childhood cases have also been observed. Common symptoms include a loss of coordination which is often seen in walking, and slurred speech. ADCA primarily affects the cerebellum, as well as, the spinal cord. Some signs and symptoms are:
Most cases of autosomal recessive cerebellar ataxia are early onset, usually around the age of 20. People with this type of ataxia share many characteristic symptoms including:
- frequent falls due to poor balance
- imprecise hand coordination
- postural or kinetic tremor of extremities or trunk
- dysarthria
- dysphasia
- vertigo
- diplopia
- lower extremity tendon reflexes
- dysmetria
- minor abnormalities in ocular saccades
- attention defects
- impaired verbal working memory and visuospatial skills
- Normal life expectancy
Autosomal recessive ataxias are generally associated with a loss of proprioception and vibration sense. Arreflexia is more common in autosomal recessive ataxia than autosomal dominant ataxias. Also, they tend to have more involvement outside of the nervous system. Mutations in subunit of the mitochondrial DNA polymerase (POLG) have been found to be a potential cause of autosomal recessive cerebellar ataxia.
Onset of symptoms usually occur in early adulthood and is characterized by intention tremor, progressive ataxia, convulsions, and myoclonic epileptic jerks.
Tremors usually affect one extremity, primarily the upper limb, and eventually involve the entire voluntary motor system. Overall, the lower extremity is usually disturbed less often than the upper extremity.
Additional features of the syndrome include: an unsteady gait, seizures, muscular hypotonia, reduced muscular coordination, asthenia, adiadochokinesia and errors with estimating range, direction, and force of voluntary movements. Mental deterioration can occur, however it is rare.
SCA6 is typified by progressive and permanent cerebellar dysfunction. These cerebellar signs include ataxia and dysarthria, likely caused by cerebellar atrophy. Prior to diagnosis and the onset of major symptoms, patients often report a feeling of "wooziness" and momentary imbalance when turning corners or making rapid movements. The age at which symptoms first occur varies widely, from age 19 to 71, but is typically between 43 and 52. Other major signs of SCA6 are the loss of vibratory and proprioceptive sensation and nystagmus.
While most patients present with these severe progressive symptoms, others, sometimes within the same family, display episodic non-progressive symptoms more similar to episodic ataxia. Still others present with symptoms common to both SCA6 and familial hemiplegic migraine.
Patients typically complain of muscle stiffness that can continue to focal weakness. This muscle stiffness cannot be walked off, in contrast to myotonia congenita. These symptoms are increased (and sometimes induced) in cold environments. For example, some patients have reported that eating ice cream leads to a stiffening of the throat. For other patients, exercise consistently induces symptoms of myotonia or weakness. Typical presentations of this are during squatting or repetitive fist clenching. Some patients also indicate that specific foods are able to induce symptoms of paramyotonia congenita. Isolated cases have reported that carrots and watermelon are able to induce these symptoms. The canonical definition of this disorder precludes permanent weakness in the definition of this disorder. In practice, however, this has not been strictly adhered to in the literature.
Typically, episodic ataxia presents as bouts of ataxia induced by startle, stress, or exertion. Some patients also have continuous tremors of various motor groups, known as myokymia. Other patients have nystagmus, vertigo, tinnitus, diplopia or seizures.
Harding ataxia, also known as Early onset cerebellar ataxia with retained reflexes (EOCARR), is an autosomal recessive cerebellar ataxia originally described by Harding in 1981. This form of cerebellar ataxia is similar to Friedreich ataxia including that it results in poor reflexes and balance, but differs in several ways, including the absence of diabetes mellitus, optic atrophy, cardiomyopathy, skeletal abnormalities, and the fact that tendon reflexes in the arms and knees remain intact. This form of ataxia is characterized by onset in the first 20 years, and is less severe than Friedreich ataxia. Additional cases were diagnosed in 1989, 1990, 1991, and 1998.
Spastic ataxia-corneal dystrophy syndrome (also known as Bedouin spastic ataxia syndrome) is an autosomally resessive disease. It has been found in an inbred Bedouin family. It was first described in 1986. A member of the family who was first diagnosed with this disease also had Bartter syndrome. It was concluded by its first descriptors Mousa-Al et al. that the disease is different from a disease known as corneal-cerebellar syndrome that had been found in 1985.
Symptoms include spastic ataxia, cataracts, macular corneal dystrophy and nonaxial myopia. Mental development is normal.
Paramyotonia congenita (PC), also known as paramyotonia congenita of von Eulenburg or Eulenburg disease, is a rare congenital autosomal dominant neuromuscular disorder characterized by “paradoxical” myotonia. This type of myotonia has been termed paradoxical because it becomes worse with exercise whereas classical myotonia, as seen in myotonia congenita, is alleviated by exercise. PC is also distinguished as it can be induced by cold temperatures. Although more typical of the periodic paralytic disorders, patients with PC may also have potassium-provoked paralysis. PC typically presents within the first decade of life and has 100% penetrance. Patients with this disorder commonly present with myotonia in the face or upper extremities. The lower extremities are generally less affected. While some other related disorders result in muscle atrophy, this is not normally the case with PC. This disease can also present as hyperkalemic periodic paralysis and there is debate as to whether the two disorders are actually distinct.
SCA13 is typified by early onset, mildly progressive cerebellar ataxia with accompanying dysarthria, mental retardation, and nystagmus. Symptoms and age of onset can vary slightly according to the causative mutation.
Non-progressive congenital ataxia (NPCA) is a non-progressive form of cerebellar ataxia which can occur with or without cerebellar hypoplasia.
Autosomal dominant cerebellar ataxia (ADCA) is a form of spinocerebellar ataxia inherited in an autosomal dominant manner. ADCA is a genetically inherited condition that causes deterioration of the nervous system leading to disorder and a decrease or loss of function to regions of the body.
Degeneration occurs at the cellular level and in certain subtypes results in cellular death. Cellular death or dysfunction causes a break or faulty signal in the line of communication from the central nervous system to target muscles in the body. When there is impaired communication or a lack of communication entirely, the muscles in the body do not function correctly. Muscle control complications can be observed in multiple balance, speech, and motor or movement impairment symptoms. ADCA is divided into three types and further subdivided into subtypes known as SCAs (spinocerebellar ataxias).
The age of onset is in a child's infancy. Bilateral corneal opacification started in the second year of life and led to severe visual impairment. However, cornea surgery and replacement resulted in better vision.
Symptoms include a combination of spinocerebellar degeneration and corneal dystrophy. Mental retardation and slowly progressive cerebellar abnormalities were also diagnosed in patients. Other symptoms include corneal edema, thickening of Descemet membrane, and degenerative pannus. Abnormalities were found in muscle and sural nerves.
RHS type 1 is caused by the impairment of a regulatory mechanism between cerebellar and brainstem nuclei and has been associated with a wide range of diseases, including Lafora disease, dentatorubropallidoluysian atrophy, and celiac disease.
Episodic ataxia type-3 (EA3) is similar to EA1 but often also presents with tinnitus and vertigo. Patients typically present with bouts of ataxia lasting less than 30 minutes and occurring once or twice daily. During attacks, they also have vertigo, nausea, vomiting, tinnitus and diplopia. These attacks are sometimes accompanied by headaches and precipitated by stress, fatigue, movement and arousal after sleep. Attacks generally begin in early childhood and last throughout the patients' lifetime. Acetazolamide administration has proved successful in some patients. As EA3 is extremely rare, there is currently no known causative gene. The locus for this disorder has been mapped to the long arm of chromosome 1 (1q42).
Symptoms typically begin sometime between the ages of 5 to 15 years, but in Late Onset FA may occur in the 20s or 30s. Symptoms include any combination, but not necessarily all, of the following:
- Muscle weakness in the arms and legs
- Loss of coordination
- Vision impairment
- Hearing impairment
- Slurred speech
- Curvature of the spine (scoliosis)
- High plantar arches (pes cavus deformity of the foot)
- Diabetes (about 20% of people with Friedreich's ataxia develop carbohydrate intolerance and 10% develop diabetes mellitus)
- Heart disorders (e.g., atrial fibrillation, and resultant tachycardia (fast heart rate) and hypertrophic cardiomyopathy)
It presents before 22 years of age with progressive staggering or stumbling gait and frequent falling. Lower extremities are more severely involved. The symptoms are slow and progressive. Long-term observation shows that many patients reach a plateau in symptoms in the patient's early adulthood. On average, after 10–15 years with the disease, patients are usually wheelchair bound and require assistance with all activities of daily living.
The following physical signs may be detected on physical examination:
- Cerebellar: nystagmus, fast saccadic eye movements, truncal ataxia, dysarthria, dysmetria.
- Lower motor neuron lesion: absent deep tendon reflexes.
- Pyramidal: extensor plantar responses, and distal weakness are commonly found.
- Dorsal column: Loss of vibratory and proprioceptive sensation occurs.
- Cardiac involvement occurs in 91% of patients, including cardiomegaly (up to dilated cardiomyopathy), symmetrical hypertrophy, heart murmurs, and conduction defects. Median age of death is 35 years, while females have better prognosis with a 20-year survival of 100% as compared to 63% in men.
20% of cases are found in association with diabetes mellitus.
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.
Spinocerebellar ataxia type 13 (SCA13) is a rare autosomal dominant disorder, which, like other types of SCA, is characterized by dysarthria, nystagmus, and ataxia of gait, stance and the limbs due to cerebellar dysfunction. Patients with SCA13 also tend to present with epilepsy, an inability to run, and increased reflexes. This cerebellar dysfunction is permanent and progressive. SCA13 is caused by mutations in KCNC3, a gene encoding a voltage-gated potassium channel K3.3. There are two known mutations in this gene causative for SCA13. Unlike many other types of SCA, these are not polyglutamine expansions but, rather, point mutations resulting in channels with no current or altered kinetics.
Bhaskar–Jagannathan has symptoms such as long fingers, thin fingers, poor balance, incoordination, high levels of amino acids in urine, cataracts during infancy, and ataxia. Ataxia, which is a neurological sign and symptom made up of gross incoordination of muscle movements and is a specific clinical manifestation
Acute cerebellar ataxia usually follows 2–3 weeks after an infection. Onset is abrupt. Vomiting may be present at the onset but fever and nuchal rigidity characterestically are absent. Horizontal nystagmus is present is approximately 50% of cases.
- Truncal ataxia with deterioration of gait
- Slurred speech and nystagmus
- Afebrile
Learning disabilities and developmental delays are often seen in children with NARP, and older individuals with this condition may experience a loss of intellectual function (dementia). Other features of NARP include seizures, hearing loss, and abnormalities of the electrical signals that control the heartbeat (cardiac conduction defects). These signs and symptoms vary among affected individuals.
The combination of muscular hypotonia and fixed dilated pupils in infancy is suspicious of Gillespie syndrome. Early onset partial aniridia, cerebellar ataxia, and mental retardation are hallmark of syndrome. The iris abnormality is specific and seems pathognomonic of Gillespie syndrome. The aniridia consisting of a superior coloboma and inferior iris hypoplasia, foveomacular dysplasia.
Atypical Gillespie syndrome associated with bilateral ptosis, exotropia, correctopia, iris hypoplasia, anterior capsular lens opacities, foveal hypoplasia, retinal vascular tortuosity, and retinal hypopigmentation.
Neurological signs ar nystagmus, mild craniofacial asymmetry, axial hypotonia, developmental delay, and mild mental retardation. Mariën P did not support the prevailing view of a global mental retardation as a cardinal feature of Gillespie syndrome but primarily reflect cerebellar induced neurobehavioral dysfunctions following disruption of the cerebrocerebellar anatomical circuitry that closely resembles the "cerebellar cognitive and affective syndrome" (CeCAS).
Congenital pulmonary stenosis and helix dysplasia can be associated.