Information about NAF, HA & OPCA

National Ataxia Foundation (NAF)

What is the National Ataxia Foundation?
The National Ataxia Foundation is a nonprofit organization established in 1957 with the primary mission of encouraging and supporting research into Hereditary Ataxia, a group of neurological disorders which are chronic and progressive conditions affecting coordination. There are more than 45 affiliated chapters and support groups throughout the U.S. and Canada.
 
Who is NAF for?
An estimated 150,000 people in the United States are affected by the hereditary and sporadic ataxias. They strike without regard to age, gender, or race. NAF's members include:
 
(For people who have ataxia as a symptom of other medical conditions such as head injury, stroke, MS, or alcoholism, we recommend that you contact the organization related to your specific condition for the most up-to-date information. We will be happy to provide you with appropriate addresses and telephone numbers if needed.)
 
What does NAF do?
NAF's programs, funded through contributions and membership dues, include:
 
NAF keeps its members informed through its quarterly publication, GENERATIONS. Also, by providing access to ELECTRONIC NAF, offers additional support and information resources.

HEREDITARY ATAXIA (HA)

To See a short video about HA & NAF go here

An estimated 150,000 people in the United States are affected by the hereditary and sporadic ataxias, a group of neurological disorders having ataxia (incoordination) as a common symptom. Hereditary ataxia affects the cerebellum and spinal cord and is passed from one generation to the next through a defective gene. The two most prevalent types of hereditary ataxia are Friedreich's (recessive) ataxia and Marie's (dominant) ataxia. Also common are the sporadic ataxias which occur spontaneously in individuals with no known family history of ataxia. You may consult a more complete ataxia classification, provided by the Department of Neurology at Washington University, School of Medicine.

 
Olivopontocerebellar Atrophy (OPCA)
 
Background: In 1900, Dejerine and Thomas first introduced the term olivopontocerebellar atrophy (OPCA). Since then, the classiication of idiopathic acquired ataxias has evolved a great deal. The initial cases of Dejerine and Thomas involved 2 middle-aged patients with chronic progressive cerebellar degeneration and autopsy findings of gross atrophy of the pons, cerebellum, middle cerebellar peduncle, and inferior olives.
 
OPCA has not been proven to be a single entity. The nosology of these disorders has been extremely confusing, as the OPCAs overlap with spinocerebellar atrophies (SCAs) and multiple system atrophies (MSAs). Clinical distinction of these entities is based on the dominant feature, which may be cerebellar ataxia (observed in OPCA, SCA, and MSA), parkinsonism (observed in MSA), or autonomic failure (observed in MSA). The term OPCA has been retained to describe a form of progressive ataxia distinguished by pontine flattening and cerebellar atrophy on brain imaging studies and at autopsy. Thus defined, OPCA also may qualify as an SCA or as an MSA.

 While MSAs are sporadic by definition, the genetic bases of the SCAs are increasingly well defined. Since OPCA may exist as a sporadic or inherited disease, categorizing sporadic OPCA as MSA and inherited OPCA s SCA may be appropriate. Differences between sporadic and inherited OPCA in microscopic pathology support this division.

When faced with an adult having progressive ataxia suggestive of OPCA, the role of the clinician includes (1) excluding readily treatable alternative diagnoses, (2) discussing the value of genetic testing with patients in whom such testing is informative, (3) managing symptoms, and (4) advising the patient and family regarding natural history and the need to plan for the future. No definitive therapy for OPCA exists.

 SYMPTOMS

Olivopontocerebellar Atrophy (OPCA) is characterized by loss of nerve cells (neurons) in the cortex of the brain, base of the pons section of brainstem (basis pontis), and inferior olivary nuclei which is a prominence on the surface of the lower part of the brain (medulla oblangata). Loss of these neurons results in impaired muscle coordination (ataxia), tremor, involuntary movement, and a speech disturbance (dysarthria). Five clinical types of OPCA have been described, depending on additional findings, such as sensory loss, retinal degeneration, ophthalmoplegia, and extrapyramidal signs. However, cases have occurred which have defied classification in any of these five categories. A wide variation in severity and age of onset may be found in any of the five recognized classifications of Olivopontocerebellar Atrophy.

Olivopontocerebellar Atrophy I (Menzel type OPCA) 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. Involuntary movements (chorea) may also occur.

Olivopontocerebellar Atrophy II (OPCA II, Fickler-Winkler or Dejerine- Thomas type) differs from OPCA type I by 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 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 and abnormal sensation, rigidity and mental deterioration. This disorder usually begins during adult life. Walking, writing and speech often become difficult as the disorder progresses.

A personal note:  There are more Subdivisions being classified all the time, this treatise is forshortened because these classifications represent a majority of the disorder Subdivisions, though the type of OPCA plauging my family is yet to be found, and thus we wait for the discovery of the gene which is responsible for my disease. Which will lead to tests which can be done on my two children and perhaps a cure.

CAUSES

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Four of the five identified forms of Olivopontocerebellar Atrophy (OPCA) are inherited as autosomal dominant traits. OPCA II is inherited as an autosomal recessive trait.

Human traits including the classic genetic diseases, are the product of the interaction of two genes for that condition, 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 the appearance of the disease. The risk of transmitting the disorder from affected parent to offspring is 50 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 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 (for that particular trait).)

The defective gene that causes Olivopontocerebellar Atrophy I (Spinocerebellar Ataxia Type I [SCA1]) is thought to be located on the short arm of chromosome 6 (p23). Some studies suggest that this defective gene may be very unusual. It may produce varying amounts of extra genetic material (trinucleotide repeats) that may be responsible for the severity of symptoms as well as the age of onset. Research suggests that people who have symptoms of this disease early in life may have a larger gene size than those with late-onset disease.

The defective gene that causes Olivopontocerebellar Atrophy II (Spinocerebellar Ataxia Type II [SCA2]) is thought to be located on the short arm of chromosome 6 (6p23).

The defective gene that causes Olivopontocerebellar Atrophy III is believed to be located on the short arm of chromosome 3 (3p21.1-p12).

The defective gene believed to cause Spinocerebellar Ataxia Type IV (SCA4) is located on the long arm of chromosome 16 (16q22.1).

The defective gene believed to cause Spinocerebellar Ataxia Type V (SCA5) is located on the centromeric region of chromosome 11 (11p11-q11).

The defective gene believed to cause Spinocerebellar Ataxia Type VI (SCA6) is located on the short arm of chromosome 19 (19p13).

The defective gene believed to cause Spinocerebellar Ataxia Type VII (SCA7) is located on the short arm of chromosome 3 (3p12-p13).

Affected Population

Olivopontocerebellar Atrophy is a group of rare disorders which usually affect males and females in equal numbers.
 
Related Disorders
 
Symptoms of the following disorders can be similar to those of Olivopontocerebellar Atrophy. Comparisons may be useful for a differential diagnosis:
 
Ataxia means walking with an unsteady gait caused by the failure of muscular coordination or irregularity of muscular action. There are many forms of Ataxia. Some ataxias are hereditary, some have other causes and sometimes ataxia can be a symptom of other disorders. To locate information about other types of ataxias, choose "Ataxia" as your search term in the Rare Disease Database.
 
Friedreich's Ataxia is a 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 may develop. Various transitional and overlapping forms of Friedreich's Ataxia can occur. Although no specific treatment can stop the progression of this 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 different forms of hereditary Ataxia. It usually begins during childhood or the teen years. (For more information on this disorder, choose "Friedrich" as your search term in the Rare Disease Database.)
 
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. (For more information on this disorder, choose "Marie" as your search term in the Rare Disease Database.)
 
Charcot-Marie-Tooth Disease (CMT) is a hereditary neurological disorder characterized by weakness and atrophy, primarily in the legs. Disappearance of the fatty shield surrounding the nerve cells (segmental demyelination of peripheral nerves), and associated degeneration of part of the nerve cells (axons) characterize this disorder. (For more information on this disorder, choose "CMT" as your search term in the Rare Disease Database.)
 
Ataxia Telangiectasia, also known as Louis-Bar Syndrome, is an inherited 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). (For more information on this disorder, choose "Louis- Bar" as your search term in the Rare Disease Database.)
 
Standard Therapies
 
Treatment of Olivopontocerebellar Atrophy is symptomatic and supportive. Continuous medical supervision to avoid potential complications involving the heart, lungs, spine, bones and muscles is recommended. Prevention of infection is a challenge in the care of people in the advanced stages of Olivopontocerebellar Atrophy. Physical therapy may be recommended by a physician.
 
There are genetic tests available for some types of Spinocerebellar Ataxia. The diagnosis of Spinocerebellar Ataxia Types I, II, and III can be confirmed with a standard blood test. Genetic testing may be developed for other types of SCA.
 
Drugs may be useful in treating some symptoms. Propranalol may be effective against static tremors, and less often against intention tremors. Static tremors can occur when the affected individual is not moving, whereas intention tremors occur when the patient makes intentional movements. Dantrolene sodium may help some patients with muscle spasms of the legs. These drugs should be carefully monitored by a physician to limit the possibility of toxicity. Genetic counseling is recommended for patients and their families. Other treatment is symptomatic and supportive.
 
Investigational Therapies
 
Research on genetic disorders and their causes is ongoing. The National Institutes of Health (NIH) is sponsoring the Human Genome Project which is aimed at mapping every gene in the human body and learning why they sometimes malfunction. It is hoped that this new knowledge will lead to prevention and treatment of genetic and familial disorders in the future.
 
Olivopontocerebellar Atrophy patients may be treated for spasticity using the drug baclofen. Other experimental drugs, cell cultures, and analysis of central nervous system tissues are also under study.
 
Researchers at the National Institutues of Health are conducting clinical trials to locate the genes responsible for a group of neurodegenerative disorders called the hereditary ataxias.
 
NORD does not promote, endorse or encourage participation in any specific medical research study. This information is presented to further scientific understanding that could lead to prevention, treatment, and/ or cure of rare disorders. NORD recommends that anyone interested in participating in a clinical research program seek the advice or counsel of his or her own personal physician(s).
 
This disease entry is based upon medical information available through 03 Jan 2002. 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
 
 
Some of this information was provided by the National Organization for Rare Disorders, P.O. Box 8923, New Fairfield, CT 06812-8923, phone: (203) 746-6518, web site: www.rarediseases.org, e-mail: orphan@rarediseases.org.
 
For more information on Olivopontocerebellar Atrophy, please contact:
 
National Ataxia Foundation (NAF)
2600 Fernbrook Lane
Suite 119
Minneapolis, MN 55447
(763) 553-0020 Phone
(763) 553-0167 Fax
e-mail : naf@ataxia.org
Home Page: http://www.naf.org
 
CLIMB (Children Living with Inherited Metabolic Diseases)
The Quadrangle
Cheshire Intl CW1 6UR
1270 250221
e-mail: Lesley@climb.org.uk
Home Page: http://www.CLIMB.org.uk
 
WE MOVE (Worldwide Education and Awareness for Movement Disorders)
Mt. Sinai Medical Center
New York NY 10029
2122418567
8004376682
e-mail: wemove@wemove.org
Home Page: http://www.wemove.org
 
March of Dimes Birth Defects Foundation
1275 Mamaroneck Avenue
White Plains NY 10605
9144287100
8886634637
e-mail: resourcecenter@modimes.org
Home Page: http://www.modimes.org
 
NIH/National Institute of Neurological Disorders and Stroke
"Brain Resources and Information Network" (BRAIN)
Bethesda MD 20824
3014965751
8003529424
e-mail: N/A
Home Page: http://www.ninds.nih.gov/
 
Metabolic Information Network (PHYSICIAN CALLS ONLY)
P.O. Box 670847
Dallas TX 75367-0847
2146962188
8009452188
e-mail: mizesg@ix.netcom.com
Home Page: N/A