CD-ROM Today (UK) (Spanish) 15/CDRT.iso/dp/0420/04205.txt

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$Unique_ID{BRK04205}
$Pretitle{}
$Title{Sanfilippo Syndrome}
$Subject{Sanfilippo Syndrome Mucopolysaccharidosis Type III MPS III
Oligophrenic Polydystrophy Polydystrophia Oligophrenia MPS Disorder Sanfilippo
Type A Sanfilippo Type B}
$Volume{}
$Log{}

Copyright (C) 1988, 1987, 1989, 1990 National Organization for Rare Disorders,
Inc.

290:
Sanfilippo Syndrome

** IMPORTANT **
It is possible the main title of the article (Sanfilippo Syndrome) is not
the name you expected.  Please check the SYNONYMS listing to find the
alternate names and disorder subdivisions covered by this article.

Synonyms

     Mucopolysaccharidosis Type III
     MPS III
     Oligophrenic Polydystrophy
     Polydystrophia Oligophrenia
     MPS Disorder

DISORDER SUBDIVISIONS

     Sanfilippo Type A
     Sanfilippo Type B

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.


Mucopolysaccharidoses (MPS Disorders) are a group of rare genetic
disorders caused by the deficiency of one of ten specific lysosomal enzymes,
resulting in an inability to metabolize complex carbohydrates
(mucopolysaccharides) into simpler molecules.  The accumulation of these
large, undegraded mucopolysaccharides in the cells of the body causes a
number of physical symptoms and abnormalities.

Sanfilippo Syndrome (MPS III), an autosomal recessive hereditary
disorder, is characterized by severe mental deterioration, mild physical
defects and the excretion of heparan sulfate in the urine.  There are four
types of Sanfilippo Syndrome; types A and B are the most common forms.

Symptoms

Patients with Sanfilippo Syndrome (MPS Type III) usually appear normal at
birth, but mental retardation is usually evident by age 3-5 years.  Mental
and motor development reach a peak by 3-6 years of age after which behavioral
disturbances and intellectual decline usually occur.

Growth is usually minimally affected; the head may be enlarged, and
abnormal hairiness (hirsutism) may occur.  Mild coarsening of facial
features, limitation of joint mobility and moderate enlargement of the liver
and spleen (hepatosplenomegaly) also characterize this disorder.  Deafness
may also occur.

The different forms of Sanfilippo Syndrome have identical clinical
features, but can be distinguished by enzymatic assay.  Sanfilippo A is
characterized by a lack of heparan sulfate sulfatase; patients with
Sanfilippo B lack N-acetyl-alpha-glucosaminidase.  Heparan sulfate is the
only mucopolysaccharide excreted in the urine.  The deficient enzymes of the
Sanfilippo subtypes are heparan N-sulfatase (type A), N-
acethylglucosaminidase (type B), acetylcoA:  gamma-glucosamine-N-
acetyltransferase (type C), and N-acetyl-gamma-glucosamine-6-sulfatase (type
D).

Causes

All types of Sanfilippo Syndrome are autosomal recessively inherited
disorders.  (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.)

Affected Population

Sanfilippo Syndrome may affect males and females equally.  The disorder
occurs in about 1 in 50,000 live births.

Related Disorders

There are many types of Mucopolysaccharidoses.  (For more information,
choose "MPS Disorder" as your search term in the Rare Disease Database.)

Patients with MPS Type III are more similar to MPS Type II patients than
those with other forms of Mucopolysaccharidoses.

DiFerrante syndrome (mucopolysaccharidosis VIII) is a disorder described
in a single patient with clinical and biochemical features of Morquio and
Sanfilippo syndromes.  The disorder had been reported to be due to a
deficiency of glucosamine-6-sulfate sulfatase.  Subsequently, this disorder
was called MPS VIII (DiFerrante) syndrome.  Dr. DiFerrante later found that
the enzyme was normal in his patient, and the disorder had been misdiagnosed.
Therefore, DiFerrante Syndrome is not a valid medical disorder.

Therapies:  Standard

Treatment of Sanfilippo Syndrome is symptomatic and supportive.  Genetic
counseling may be helpful to the parents of patients with Sanfilippo
Syndrome.  Prenatal diagnosis is now possible for this disorder.

Therapies:  Investigational

Since prenatal diagnosis is now possible through amniocentesis and sampling
of a tissue layer in the embryo (chorionic villus sampling), new treatments
aimed at checking early development of Sanfilippo Syndrome are now under
study.  One method involves replacing defective enzymes via enzyme
replacement therapy and/or bone marrow transplants.  Scientific study of gene
replacement in animal models raises the hope that gene replacement may
someday be made available to people with genetic disorders such as Sanfilippo
Syndrome.

The Mayo Clinic is investigating the use of Alpha Interferon as a
treatment for Sanfilippo Syndrome.  For more information, physicians can
contact:

     Morie A. Gertz, M.D.
     Dept. of Hematology & Internal Medicine
     Mayo Clinic
     Rochester, MN  55905
     [phone]

This disease entry is based upon medical information available through
June 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 Sanfilippo Syndrome, please contact:

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

     MPS (Mucopolysaccharidoses) Research Funding Center, Inc.
     1215 Maxfield Road
     Hartland, MI  48029
     [phone]

     National MPS Society
     17 Kramer Street
     Hicksville, NY  11801
     [phone]

     Society of Mucopolysaccharide Diseases, Inc.
     382 Parkway Blvd.
     Flin Flon, Manitoba, Canada R8A OK4

     Society of MPS Diseases
     30 Westwood Drive
     Little Chalfont, Bucks, England

     National Digestive Diseases Information Clearinghouse
     Box NDDIC
     Bethesda, MD  20892
     [phone]

For information on genetics and genetic counseling referrals, please
contact:

     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

MPS Society Brochure.

BIRTH DEFECTS COMPENDIUM, 2nd ed.:  Daniel Bergsma, ed:  March of Dimes,
1979.  P. 731.

MENDELIAN INHERITANCE IN MAN, 6th ed.:  Victor A. McKusick; Johns Hopkins
University Press, 1983.  P. 839.