CD-ROM Today (UK) (Spanish) 15/CDRT.iso/dp/0371/03719.txt

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$Unique_ID{BRK03719}
$Pretitle{}
$Title{Epilepsy, Myoclonic Progressive Familial}
$Subject{Epilepsy Myoclonic Progressive Familial Myoclonic Epilepsy Myoclonic
Progressive Familial Epilepsy Myoclonus Epilepsy Progressive Familial
Myoclonic Epilepsy Lafora Lafora's Disease Lafora Body Disease
Unverricht-Lundborg(-Laf) Disease Baltic Myoclonus Epilepsy
Lundborg-Unverricht Disease Unverricht Disease Syndrome Myoclonic Epilepsy
Hartung Type Postanoxic Myoclonus Juvenile Myoclonic Epilepsy JME EJM
Impulsive Petit Mal Janz Syndrome Huntington's Disease Tourette Syndrome
Wilson's Disease Kufs Disease Ramsay-Hunt Syndrome}
$Volume{}
$Log{}

Copyright (C) 1990 National Organization for Rare Disorders, Inc.

781:
Epilepsy, Myoclonic Progressive Familial

** IMPORTANT **
It is possible that the main title of the article (Epilepsy, Myoclonic
Progressive Familial) is not the name you expected.  Please check the SYNONYM
listing to find the alternate names and disorder subdivisions covered by this
article.

Synonyms

     Myoclonic Epilepsy
     Myoclonic Progressive Familial Epilepsy
     Myoclonus Epilepsy
     Progressive Familial Myoclonic Epilepsy

Disorder Subdivisions:

Lafora('s) Disease (Lafora Body Disease)

Unverricht-Lundborg(-Laf) Disease (also known as Baltic Myoclonus

Epilepsy, Lundborg-Unverricht Disease, Unverricht Disease or Syndrome)

Myoclonic Epilepsy, Hartung Type

Information on the following disorders can be found in the Related
Disorders section of this report:

     Postanoxic Myoclonus
     Juvenile Myoclonic Epilepsy (JME; EJM; Impulsive Petit Mal; Janz
     Syndrome)
     Huntington's Disease
     Tourette Syndrome
     Wilson's Disease
     Kufs Disease
     Ramsay-Hunt Syndrome

General Discussion

** REMINDER **
The information contained in the Rare Disease Database is provided for
educational purposes only.  It should not be used for diagnostic or treatment
purposes.  If you wish to obtain more information about this disorder, please
contact your personal physician and/or the agencies listed in the "Resources"
section of this report.

Myoclonic Progressive Familial Epilepsy is a disorder of the central
nervous system.  It begins in childhood, and is progressive.  The main
characteristic of this form of myoclonus is jerking involuntary muscle
movements may involve muscles in the limbs or the whole body.  As the disease
progresses, there is impairment of mental capabilities, which may lead to
loss of reason (dementia).  Myoclonic epilepsy can be a symptom of many
central nervous system disorders.

Symptoms

There are three different types of Myoclonic Progressive Familial Epilepsy.

In Lafora's Disease, onset usually occurs around the age of 15 in the
form of grand mal seizures and/or myoclonus.  Lafora's Disease may be
detected by the presence of particles (Lafora bodies) in various cells
including the nervous system (such as the brain, spinal cord, and nerve
cells), retina (part of the eye), heart, muscle (or muscle fibers), and
liver.  Diagnosis of Lafora's Disease may be made through a biopsy to
determine the presence of Lafora bodies in tissue.  As Lafora's Disease
progresses, mental deterioration occurs.  Grand mal seizures occur, which are
characterized by convulsive muscle spasms, loss of consciousness, and
confusion.

The Unverricht-Lundborg type of epilepsy is frequently found in persons
of Finnish and Swedish heritage.  Onset of this disorder may occur anywhere
between the ages of six and thirteen.  Its features are convulsions, with
myoclonus beginning one to five years later.  Muscle spasms occur in the
limbs and may be seen as minor twitching motions; later they may become
violent enough to cause the patient to fall to the ground.  Mental
deterioration occurs as the disease progresses.  The duration and seriousness
of the disorder is variable.  In advanced cases, inability to coordinate
voluntary muscle movements (cerebellar ataxia) occurs.  Very rarely, deafness
may occur, especially when cerebellar ataxia is present.  Emotional
instability is common.  In Unverricht's, no particles can be found in cells
that cause the disease (such as in Lafora's disease).  However, there is a
loss of nerve cells in the area of the brain that is concerned with muscle
coordination and balance.  Changes in the environment like flashing lights or
the flickering of sunlight may cause the worst symptoms (stimulus-sensitive
myoclonus).  Other features are generalized tonic-clonic seizures which are
sometimes combined with absence attacks (petit mal).  These types of seizures
may be documented by EEG readings.

Myoclonic Epilepsy-Hartung Type is different has an autosomal dominant
inheritance and no Lafora bodies are found, and only sporadic loss or
deterioration of cells (diffuse atrophy) is present in the patient.

(For more information on these and other types of seizures, choose
"Epilepsy" as your search term in the Rare Disease Database).

Causes

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.

Myoclonic Progressive Familial Epilepsy is inherited through autosomal
recessive genes.  In recessive disorders, such as Lafora's Disease and
Unverricht's Disease, 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.

Myoclonic Epilepsy-Hartung Type is inherited through an autosomal
dominant gene.  In autosomal dominant disorders, a single abnormal gene,
contributed by either parent, overrides the normal gene contributed by the
other parent, causing disease.  Individuals with one affected parent have a
50% chance of inheriting the disorder.  Males and females will be affected in
equal numbers.

Affected Population

Myoclonic Progressive Familial Epilepsy affects males and females in equal
numbers.  It begins during childhood and is a rare form of epilepsy.

Related Disorders

Symptoms of the following disorders can be similar to those of Myoclonic
Progressive Familial Epilepsy.  Comparisons may be useful for a differential
diagnosis:

In general, myoclonus is a group of movement disorders characterized by
sudden, involuntary contractions of a skeletal muscle or group of muscles.
It may be divided into two groups, rhythmical and arrhythmic myoclonus.
Myoclonus may accompany a number of neurological diseases including seizure
disorders, brain injuries, hereditary brain disorders, viral infections, and
brain tumors.  Hereditary, and idiopathic forms also exist.  In Postanoxic
Myoclonus the disorder begins after the brain is deprived of oxygen.  (For
more information about other types of myoclonus, choose "myoclonus" as your
search term in the Rare Disease Database).

In Juvenile Myoclonic Epilepsy, the age of onset is early.  It is
characterized by the presence of isolated myoclonic jerks that do not
necessarily lead to major seizures.  These symptoms usually occur in the
morning.  There may be a record of epilepsy in the family history.  In some
cases there is evidence that this form of epilepsy is inherited through
autosomal recessive genes.  Juvenile Myoclonic Epilepsy is often diagnosed
through use of the electroencephalograph (EEG) which demonstrates evidence of
the illness even when no seizures are present.  Occasionally, some family
members who show no outward symptoms of the disorder will show the same EEG
characteristics.  This disorder is chronic but not progressive.

Huntington's Disease (also known as Huntington's Chorea) is an inherited,
progressively degenerative neurological illness.  Those affected experience
abnormal involuntary movements (chorea), loss of motor control, changes in
gait, loss of memory, and eventual loss of both mental capacity and physical
control.  In general, onset of HD occurs in adults between thirty and fifty
years of age and runs a progressive course, severely weakening patients
usually over a ten to twenty year period.  (For more information on this
disorder, choose "Huntington's Disease" as your search term in the Rare
Disease Database).

Tourette Syndrome is a neurological movement disorder which begins in
childhood between the ages of 2 and 16.  The disease is characterized by
involuntary abrupt muscular movements called " tics", and uncontrollable
vocal sounds.  Sometimes inappropriate words may occur.  Tourette Syndrome is
not a degenerative disorder and those affected can expect to live a normal
life span.  (For more information on this disorder, choose "Tourette
Syndrome" as your search term in the Rare Disease Database).

Wilson's Disease is a rare genetic disorder characterized by excess
storage of copper in the body tissues, particularly in the liver, brain, and
corneas of the eyes.  It eventually leads to liver disease, neurological
abnormalities such as seizures, and a characteristic rusty-brown colored ring
in the cornea of the eyes known as Kayser-Fleischer rings.  Involuntary
abnormal movements, particularly tremor and chorea, and behavioral changes
are early symptoms of this disorder.  (For more information on this disorder,
choose "Wilson" as your search term in the Rare Disease Database).

The following disorders may be associated with Myoclonic Progressive
Familial Epilepsy.  They are not necessary for a differential diagnosis:

Kufs Disease is a very rare disorder of the central nervous system marked
initially by progressive weakness with diminished muscle coordination,
seizures, rapid involuntary jerky movements and rarely blindness.  This
disorder can be inherited as either a dominant or recessive trait and is
usually slowly progressive.  (For more information on this disorder, choose
"Kufs Disease" as your search term in the Rare Disease Database).

Ramsay-Hunt Syndrome is an autosomal dominant disorder in which epilepsy
and myoclonus accompany significant spinocerebellar degeneration and other
progressive neurological abnormalities.  (For more information on this
disorder, choose "Ramsay" as your search term in the Rare Disease Database).

Therapies:  Standard

Treatment of Myoclonic Progressive Familial Epilepsy includes valproic acid
and clonazepam which are anticonvulsant drugs.

Therapies:  Investigational

Treatment of Myoclonic Progressive Familial Epilepsy for patients who
continue to have seizures despite anticonvulsant medication may include the
drug zonisamide along with valproic acid and a bezodiazepine drug.

Genetic counseling may be of benefit for patients and their families.
Other treatment is symptomatic and supportive.

This disease entry is based upon medical information available through
November 1990.  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 Myoclonic Progressive Familial Epilepsy, please
contact:

     National Organization for Rare Disorders
     P.O. Box 8923
     New Fairfield, CT 06812-1783
     [phone]

     NIH/National Institute of Neurological Disorders & Stroke (NINDS)
     9000 Rockville Pike
     Bethesda, MD  20892
     [phone]
     [phone]

     The Epilepsy Foundation of America
     4341 Garden City Drive
     Landover, MO 20785
     [phone]
     [phone]

For genetic information and genetic counseling referrals:

     March of Dimes Birth Defects Foundation
     1275 Mamaroneck Avenue
     White Plains, NY  10605
     [phone]

     Alliance of Genetic Support Groups
     35 Wisconsin Circle, Suite 440
     Chevy Chase, MD  20815
     (800) 336-GENE
     [phone]

References

MENDELIAN INHERITANCE IN MAN, 8th ed.:  Victor A. McKusick; Johns Hopkins
University Press, 1986.  Pp. 506, 893, 1090-1091.

DIAGNOSIS OF LAFORA DISEASE BY SKIN BIOPSY.  J.W. White Jr. et al.; J
Cutan Pathol (June 1989; issue 15 (3)).  Pp. 171-175.

JUVENILE MYOCLONIC EPILEPSY.  M.J. Clement et al.; Arch Dis Child
(September , 1988; issue 63 (9)).  Pp.1049-1053.

JUVENILE MYOCLONIC EPILEPSY:  AN AUTOSOMAL RECESSIVE DISEASE.  C.P.
Panayiotopoulos et al.; Ann Neurol (May 1989; issue 25 (5)).  Pp. 440-443.

JUVENILE MYOCLONIC EPILEPSY:  CHARACTERISTICS OF A PRIMARY GENERALIZED
EPILEPSY.  F.E. Dreifuss; Epilepsia (1989; issue 30 (4)).  Pp. 1-7, 24-27.

PROGRESSIVE MYOCLONUS EPILEPSY TREATED WITH ZONISAMIDE.  T.R. Henry et
al.; Neurology (June 1988; issue 38 (6)).  Pp. 928-931.

VALPROATE MONOTHERAPY IN CHILDREN.  J.V. Murphy; Am J Med (January 25,
1988; issue 84 (1A)).  Pp. 17-22.