home *** CD-ROM | disk | FTP | other *** search
- $Unique_ID{BRK04092}
- $Pretitle{}
- $Title{Pelizaeus-Merzbacher Brain Sclerosis}
- $Subject{Pelizaeus-Merzbacher Brain Sclerosis Diffuse Familial Brain Sclerosis
- Aplasia, Axialis Extracorticales Congenita Sudanophilic Leukodystrophy
- Pelizaeus-Merzbacher Disease}
- $Volume{}
- $Log{}
-
- Copyright (C) 1986, 1987, 1990 National Organization for Rare Disorders,
- Inc.
-
- 158:
- Pelizaeus-Merzbacher Brain Sclerosis
-
- ** IMPORTANT **
- It is possible that the main title of the article (Pelizaeus-Merzbacher
- Brain Sclerosis) is not the name you expected. Please check the SYNONYM
- listing to find the alternate names and disorder subdivisions covered by this
- article.
-
- Synonyms
-
- Diffuse Familial Brain Sclerosis
- Aplasia, Axialis Extracorticales Congenita
- Sudanophilic Leukodystrophy
- Pelizaeus-Merzbacher Disease
-
- 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.
-
-
- Pelizaeus-Merzbacher Brain Sclerosis is a progressive, degenerative
- central nervous system disease in which coordination, motor abilities, and
- intellectual function deteriorate. It often progresses rapidly, although
- some patients have lived to old age. The disorder almost always occurs in
- males.
-
- Symptoms
-
- Evidence of Pelizaeus-Merzbacher Brain Sclerosis usually appears in early
- infancy, although onset is later in one form. The child fails to develop
- normal control of head movements and grows slowly. The eyes wander aimlessly
- or in circular movements. Later symptoms include tremor, various involuntary
- movements, grimacing, weakness, unsteady gait, and muscle contractures. In
- cases with later onset, speech usually deteriorates. As time progresses,
- legs and then the arms can become spastic, and mental functions deteriorate.
- Some patients experience convulsions. Skeletal deformation may result from
- abnormal muscular stresses on bone.
-
- Pathologic changes in the brain consist of destruction of the myelin
- sheath (a kind of insulation) surrounding the axons of the nerve cells (the
- white matter of the brain). These changes occur in subcortical parts of the
- cerebrum, the cerebellum, and the brainstem. Breakdown products of myelin
- also accumulate in the brain. These stain characteristically.
-
- Causes
-
- The reasons for the degeneration of the white matter of the brain are not
- understood. Pelizaeus-Merzbacher Brain Sclerosis is hereditary. Infantile
- forms are either autosomal recessive or X-linked.
-
- 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 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.
-
- X-linked recessive disorders are conditions which are coded on the X
- chromosome. Females have two X chromosomes, but males have one X chromosome
- and one Y chromosome. Therefore in females, disease traits on the X
- chromosome can be masked by the normal gene on the other X chromosome. Since
- males have only one X chromosome, if they inherit a gene for a disease
- present on the X, it will be expressed. Men with X-linked disorders transmit
- the gene to all their daughters, who are carriers, but never to their sons.
- Women who are carriers of an X-linked disorder have a fifty percent risk of
- transmitting the carrier condition to their daughters, and a fifty percent
- risk of transmitting the disease to their sons.
-
- A form with adult onset is autosomal dominant. In dominant disorders, a
- single copy of the disease gene (received from either the mother or father)
- will be expressed "dominating" the normal gene and resulting in appearance of
- the disease. The risk of transmitting the disorder from affected parent to
- offspring is 50% for each pregnancy regardless of the sex of the resulting
- child.
-
- Affected Population
-
- One form of Pelizaeus-Merzbacher Brain Sclerosis affects male infants. Other
- forms affect infants or adults of both sexes.
-
- Related Disorders
-
- Pelizaeus-Merzbacher Brain Sclerosis belongs to a group of degenerative brain
- diseases known as leukodystrophies. These are characterized by destruction
- of the white matter of the brain, and include such diseases as Krabbe's,
- Schilder's, Adrenoleukodystrophy, and several others.
-
- Therapies: Standard
-
- Treatment for Pelizaeus-Merzbacher Brain Sclerosis is symptomatic. Supportive
- care, including emotional support for family members, is recommended as
- needed.
-
- Therapies: Investigational
-
- Current research is directed toward the identification of the gene that
- causes Pelizaeus-Merzbacher Brain Sclerosis. When the gene is located,
- scientists may be able to determine the exact cause of the symptoms, which
- will hopefully lead to development of new treatments for this disease.
-
- This disease entry is based upon medical information available through
- January 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 Pelizaeus-Merzbacher Brain Sclerosis, please
- contact:
-
- National Organization for Rare Disorders (NORD)
- P.O. Box 8923
- New Fairfield, CT 06812-1783
- (203) 746-6518
-
- United Leukodystrophy Foundation
- 2304 Highland Drive
- Sycamore, IL 60178
- (815) 895-3211
- (800) 728-5483
-
- NIH/National Institute of Neurological Disorders & Stroke (NINDS)
- 9000 Rockville Pike
- Bethesda, MD 20892
- (301) 496-5751
- (800) 352-9424
-
- International Tremor Foundation
- 360 W. Superior St.
- Chicago, IL 60610
- (312) 664-2344
-
- Research Trust for Metabolic Diseases in Children
- Golden Gates Lodge, Weston Rd.
- Crewe CW1 1XN, England
- Telephone: (0270) 250244
-
- Association Europeenne contre les Leucodystrophies
- 7 Rue Pasteur
- 54000 NANCY
- France
-
- References
-
- CECIL TEXTBOOK OF MEDICINE, 18th ed.: James B. Wyngaarden, and Lloyd H.
- Smith, Jr., Eds.: W. B. Saunders Co., 1988. P. 2216.
-
-