Hereditary Ataxia
Hereditary Ataxia is a group of rare genetic neuromuscular disorders.
It is characterized by degenerative changes in the brain and spinal cord.
It can affect a person anytime between infancy through adulthood. Major
symptoms include lack of coordination of the muscles used for voluntary
movement.
1 Synonyms
2 Symptoms
3 Causes
4 Therapies: Standard
5 Therapies: Investigational
6 Resources
7 References
Synonyms
----------------
Progressive Cerebellar Ataxia
Disorder Subdivisions:
Friedreich's Ataxia
Marie's Ataxia
Ataxia Telangiectasia
Vasomotor Ataxia
Vestibulocerebellar
Ataxiadynamia
Ataxiophemia
Olivopontocerebellar Atrophy
Charcot-Marie-Tooth Disease
Symptoms
--------
The Ataxia's are progressive neuromuscular disorders characterized by
unsteadiness in walking or tremors of the arms and legs. Depending on
which part of the brain is affected there may be muscle weakness and
wasting which usually occurs when the lower motor neurons are affected.
Some types of Ataxia may be complicated by vision disorders such as
optic atrophy, retinitis pigmentosa, ophthalmaplegia (face and eye
paralysis), nerve deafness or mental deterioration. There may also be
skeletal changes such as scoliosis (bent spine) and deformities of the
feet. Other medical problems may occur in relation to Ataxia such as
heart disease, breathing problems, bone abnormalities and diabetes.
Disorder Subdivisions:
Olivopontocerebellar Atrophy is a group of inherited forms of Ataxia
characterized by progressive neurological degeneration affecting the
olivopontocerebellar area of the brain. These inherited forms include
Menzel type I, Fickler-Winkler type II, retinal degeneration type III,
Schut- Haymaker type IV, and ophthalmoplegia (paralysis of facial and eye
muscles) type V OPCA.
Olivopontocerebellar Atrophy I (Menzel type OPCA) is inherited as a
dominant trait and usually begins in the third or fourth decades of life,
with an average onset at thirty years of age. In addition to cerebellar
degeneration, other areas of the body become affected with speech
abnormalities and/or tremors of the limbs. Involuntary movements (chorea)
may also occur.
Olivopontocerebellar Atrophy II (OPCA II, Fickler-Winkler or deJerine-
Thomas type) is inherited as a recessive trait and differs from OPCA type
I by showing a lack of involuntary movements. Onset of this disorder
usually begins at approximately fifty years of age. The exact nature of
this form of cerebellar atrophy is not well understood.
Olivopontocerebellar Atrophy III (OPCA III; OPCA with retinal degeneration)
is characterized by retinal degeneration. This form of OPCA usually
begins during middle age, although it can begin at any age. It is also
marked by blindness, tremor, weakness and impaired muscle coordination.
Olivopontocerebellar Atrophy IV (OPCA IV, Schut-Haymaker type OPCA) is
inherited as a dominant trait and is characterized by a form of paralysis
(spastic paraplegia). The atrophy seems to be limited to the inferior
olivary nucleus and cerebellum with varying involvement of the pons area
of the brain. Abnormalities of the spinal cord and some of the cranial
nerves may also occur. Symptoms usually begin at approximately twenty-five
years of age.
Olivopontocerebellar Atrophy V (OPCA V, OPCA with dementia and
extrapyramidal signs) is characterized by cerebellar atrophy, tremors,
ataxia, abnormal sensations, rigidity and mental deterioration. This
disorder is inherited as a dominant trait and usually begins during adult
life. Walking, writing and speech often become difficult as the disorder
progresses.
Charcot-Marie-Tooth Disease (also known CMT Disease and Peroneal Muscular
Atrophy) is usually inherited as a dominant trait. However, in some
families it can occur as a recessive trait or even as an X-linked trait.
This hereditary form of ataxia is characterized by weakness and atrophy,
primarily in the legs. Disappearance of the fatty shield surrounding the
nerves (segmental demyelination of peripheral nerves), and associated
degeneration of part of the nerve cells (axons) characterize this disorder.
When it is passed to offspring as an X-linked trait it affects only males.
Friedreich's Ataxia is a recessive type of hereditary neuromuscular
syndrome characterized by slow degenerative changes of the spinal cord
and the brain. Dysfunction of the central nervous system affects
coordination of the muscles in the limbs. Speech can be affected and
numbness or weakness of the arms and legs develop. Various transitional
and overlapping forms of Friedreich's Ataxia can occur. Although no
specific treatment can stop the progression of the disorder, some symptoms
can be alleviated with proper treatment. In a few cases, spontaneous
remissions may occur which can last five to ten years or sometimes longer.
This syndrome appears to be the most common of the many forms of
hereditary Ataxia. It usually begins during childhood or the teen years.
Marie's Ataxia is a neuromuscular syndrome inherited as a dominant trait.
Also known as Pierre Marie's Disease or Hereditary Cerebellar Ataxia, it
is characterized by a later onset of neurological and coordination
disturbances. The syndrome usually begins between thirty and forty years
of age and may not be as disabling as Friedreich's Ataxia. Initially,
those affected may walk unsteadily and tend to fall frequently. Loss of
coordination in the arms and speech disturbances may also occur. In later
stages slight loss of vision, and loss of pain or touch sensations, may
also occur. Tremors may develop when conscious motion is attempted.
Swallowing and clearing of secretions may eventually become difficult if
the throat muscles are affected.
Ataxia Telangiectasia, also known as Louis-Bar Syndrome, is inherited as
a recessive trait. It is a progressive cerebellar ataxia that usually
begins during infancy. It involves progressive loss of coordination in
the limbs, head and eyes with a below-normal immune response to infections.
In later stages, dilated blood vessels (telangiectasias) appear in the
eyes and skin. Individuals with this form of Ataxia are more susceptible
to sinus and lung infections and tend to have tumors (neoplasms). Ataxia
Telangiectasia may be misdiagnosed as Friedreich Ataxia until dilated
blood vessels appear in the skin (telangiectasias).
Vasomotor Ataxia is a dominant form of autonomic ataxia causing an
unsteady walk and irregularity in the circulation marked by flushing and
blanching of the skin due to spasms of the smaller blood vessels.
Vestibulocerebellar Ataxia is inherited as a dominant trait. It is due
to disease of the central vestibular system or it's cerebellar components.
Characterized by unsteady gait, incoordination of arm and leg movements
and constant movement of the eyeballs (nystagmus).
Ataxiadynamia is a lack of coordination combined with muscular weakness.
It is usually inherited as a dominant trait.
Ataxiophemia is inherited as a dominant trait. It is characterized by
incoordination of the muscles concerned in speech production.
Causes
------
Some forms of hereditary Ataxia are inherited as a dominant trait. In
other forms it may be passed to offspring through recessive genes.
Human traits, including the classic genetic diseases, are the product of
the interaction of two genes, one received from the father and one from
the mother.
In dominant disorders a single copy of the disease gene (received from
either the mother or father) will be expressed "dominating" the other
normal gene and resulting in appearance of the disease. The risk of
transmitting the disorder from affected parent to offspring is fifty
percent for each pregnancy regardless of the sex of the resulting child.
In recessive disorders, the condition does not appear unless a person
inherits the same defective gene for the same trait from each parent.
If one receives one normal gene and one gene for the disease, the person
will be a carrier for the disease, but usually will show no symptoms.
The risk of transmitting the disease to the children of a couple, both of
whom are carriers for a recessive disorder, is twenty-five percent. Fifty
percent of their children will be carriers, but healthy as described above.
Twenty-five percent of their children will receive both normal genes, one
from each parent, and will be genetically normal.
Some forms of Ataxia are not hereditary and can occur as a result of
severe infections or side effects of drugs. In many cases Ataxia is a
symptom of another neurological disorder rather than a distinct and
separate illness.
Therapies: Standard
--------------------
Treatment of Ataxia is symptomatic and supportive. Continuous medical
supervision to avoid potential complications involving the heart, lungs,
spine, bones and muscles is recommended. Mental functions usually remain
unaffected in most forms of hereditary ataxia but emotional strain can
affect patients and their families. In such cases, psychological
counseling may be helpful. Physical therapy may be helpful when recommended
by a physician. Various aids may assist muscular movement. Drugs may be
useful in treating some symptoms of Ataxia. Propanalol may be effective
against static tremors, and less often against intention tremors.
Dantrolene Sodium may help some patients with muscle spasms of the legs.
Genetic counseling will be of benefit for patients and families affected
by the hereditary ataxias.
Therapies: Investigational
---------------------------
The multiprogrammable spinal cord stimulator involves epidural spinal
electrostimulation (ESES). This is a medical device being tested for
neuromuscular disorders. The device must be surgically implanted. The
goal is to increase the range of mobility and alleviate muscle spasms and
pain. A controlled study of ESES devices is being conducted by:
Neuromed
5000 Oakes Rd.
Ft. Lauderdale, FL 33314
(305) 584-3600
Clinical trials of the orphan drug physostigmine salicylate (Antilirium)
for treatment of inherited forms of Ataxia are underway. For additional
information physicians can contact:
Forrest Pharmaceuticals
2510 Metro Boulevard
Maryland Heights, MO 64043-99
This disease entry is based upon medical information available through
June 1989. Since NORD's resources are limited, it is not possible to
keep every entry in the Rare Disease Database completely current and
accurate. Please check with the agencies listed in the Resources section
for the most current information about this disorder.
Resources
---------
For more information on Hereditary Ataxia, please contact:
National Organization for Rare Disorders (NORD)
P.O. Box 8923
New Fairfield, CT 06812-1783
(203) 746-6518
(203) 746-6927 (TDD for the hearing impaired)
National Ataxia Foundation
2600 Fernbrook Lane, Site 119
Minniapolis, MN 55447-4752
Phone: (763) 553-0020
Email: naf@ataxia.org
NIH/National Institute of Neurological Disorders & Stroke (NINDS)
9000 Rockville Pike
Bethesda, MD 20892
(301) 496-5751
(800) 352-9424
International Tremor Foundation
833 W. Washington Blvd.
Chicago, IL 60607
(312) 733-1893
For genetic information and genetic counseling referrals:
March of Dimes Birth Defects Foundation
1275 Mamaroneck Avenue
White Plains, NY 10605
(914) 428-7100
Alliance of Genetic Support Groups
35 Wisconsin Circle, Suite 440
Chevy Chase, MD 20815
(800) 336-GENE
(301) 652-5553
References
----------
MENDELIAN INHERITANCE IN MAN, 8th ed.: Victor A. McKusick; Johns Hopkins
University Press, 1986. Pp. 84.
INTERNAL MEDICINE, 2nd Ed.: Jay H. Stein, ed.-in-chief; Little, Brown
and Co., 1987. Pp.2160.
SPINOCEREBELLAR ATAXIA: LOCALIZATION OF AN AUTOSOMAL DOMINANT LOCUS
BETWEEN TWO MARKER ON HUMAN CHROMOSOME 6; S.S. Rich, et al.;
Am J Hum Genet, (October, 1987, issue 41 (4)). Pp. 524-531.
BRAIN CHOLINE ACETYLTRANSFERASE REDUCTION IN DOMINANTLY INHERITED
OLIVOPONTOCEREBELLAR ATROPHY; J.J. Kish, et al.; Ann Neurol
(August, 1987, issue 22 (2)). Pp. 272-275.