CD-ROM Today (UK) (Spanish) 15/CDRT.iso/dp/0396/03969.txt

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$Unique_ID{BRK03969}
$Pretitle{}
$Title{Marfan Syndrome}
$Subject{Marfan Syndrome Arachnodactyly Contractural Arachnodactyly
Dolichostenomelia Marfanoid Hypermobility Syndrome Acromegaly Ehlers-Danlos
Syndrome Homocystinuria Beals Syndrome Cohen Syndrome}
$Volume{}
$Log{}

Copyright (C) 1984, 1985, 1987, 1988, 1989, 1990, 1992 National
Organization for Rare Disorders, Inc.

27:
Marfan Syndrome

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

Synonyms

     Arachnodactyly
     Contractural Arachnodactyly
     Dolichostenomelia
     Marfanoid Hypermobility Syndrome

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

     Acromegaly
     Ehlers-Danlos Syndrome
     Homocystinuria
     Beals Syndrome
     Cohen 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.


Marfan Syndrome is an inherited disorder that effects the connective
tissues of the heart and blood vessels (cardiovascular system).  The
musculoskeletal system (ligaments and muscles) is also affected.  Major
symptoms also include unusual height, large hands and feet, and involvement
of the lungs and the eyes.

Symptoms

People with Marfan Syndrome are unusually tall and thin.  Both the face and
the limbs are abnormally long.  Other features may include excessive joint
mobility, flat feet, muscle weakness (hypotonia), a protruding or indented
breast bone (sternum) and curvature of the spine (scoliosis).  The teeth may
be crowded because of an abnormally high palate.  Stretch marks (striae) may
appear on the skin.

Patients with Marfan Syndrome may have significant cardiovascular
problems.  The most common of these is mitral valve prolapse, which is often
without symptoms.  Mitral valve prolapse is characterized by the incomplete
closure of the heart valve and the backward flow of blood in the heart.
Enlargement and degeneration of the aorta, aortic aneurysm (a bulge of the
wall of the aorta), and aortic regurgitation (backward flow of blood) are
also common.  Untreated, these cardiac complications account for most deaths
from Marfan Syndrome.

About 50 percent of patients with Marfan Syndrome experience an abnormal
displacement of the lens within the eyes (ectopia lentis).  Another major
symptom is nearsightedness (myopia).  Other findings that relate to the eye
may include an increased axial globe length, flatness of the cornea and
occasionally retinal detachment.  These conditions are diagnosed by an
ophthalmologist (a physician who specializes in eye disease.

Emphysema, which causes destructive changes and the loss of elasticity of
the lungs, develops in almost all patients with Marfan Syndrome.  A collapsed
lung (pneumothorax) occurs in 5 percent of patients, either spontaneously or
traumatically, and requires immediate attention.

Causes

Marfan Syndrome is inherited as an autosomal dominant trait.  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 the 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.

The single mutation that causes this disorder has been located on
chromosome 15.  Penetrance is complete but expression of symptoms (clinical
manifestations) may be variable.  Penetrance is the regularity with which an
inherited trait expresses symptoms in the person who carries the gene.

The exact nature of the connective tissue abnormalities that are present
in patients with Marfan Syndrome is not well understood by scientists.

Affected Population

Marfan Syndrome affects males and females in equal numbers.  In the United
States, about 25,000 to 30,000 people have Marfan Syndrome, many of whom have
not been diagnosed.  Early diagnosis is crucial to avoid or delay the heart
complications of Marfan Syndrome.

Related Disorders

Symptoms of the following disorders can be similar to those of Marfan
Syndrome.  Comparisons may be useful for a differential diagnosis:

Acromegaly is a slowly progressive disorder characterized by an excess of
growth hormone (GH).  An excessive amount of this hormone causes an abnormal
enlargement of the bones, especially those of the arms, legs and skull.  The
bones of the forehead and the jaw tend to be the most affected.  The jaw
protrudes and there is generally an overbite that may lead to the wide
separation of teeth.   There is thickening of the soft tissues of the body
including those of the heart.  The liver, spleen and kidneys may also become
enlarged as the disease progresses.  (For more information on this disorder,
choose "Acromegaly" as your search term in the Rare Disease Database).

Ehlers-Danlos Syndrome (EDS) describes a group of inherited disorders of
connective tissue.  The various forms are labeled I to X and the symptoms
vary according to the form of the disease, which always effects the joints
and skin.  Characteristic symptoms include very elastic, fragile skin and a
tendency toward easy bruising and bleeding.   Another major symptom is the
ability to flex the joints beyond their normal range (hyperextensibility).
Soft tumor-like growths may be present.  Facial characteristics may be normal
or the eyes may be widely spaced.  (For more information on this disorder,
choose "Ehlers-Danlos Syndrome" as your search term in the Rare Disease
Database).

Homocystinuria is a rare metabolic disorder that is characterized by an
abnormal amount of homocystine and methionine in the blood, cerebrospinal
fluid and the urine.  The symptoms of this disorder include abnormal
displacement of the lens of the eyes (ectopia lentis), cataracts, a thinning
of the bones (osteoporosis), seizures, mental retardation, blood clots in the
lungs (pulmonary emboli), and heart problems.  Patients with Homocystinuria
may have the signs and symptoms of Marfan Syndrome such as an elongated body
and extremities, a depression of the breast bone, and cardiovascular defects.
(For more information on this disorder, choose "Homocystinuria" as your
search term in the Rare Disease Database).

Beals Syndrome is a rare inherited connective tissue disorder.  The major
features of this disorder include long, thin, "spider-like" fingers and toes;
joints that are in the bent position from birth; and deformity of the ears
that causes a "crumpled" appearance.  Generally the joints that are affected
are the fingers, elbows, knees and ankles.  There may be severe curvature of
the spine (kyphoscoliosis), a forward projection of the breast bone (pectus
carinatum) and a cone-like bulge of the eye that may result in blurred vision
(keratoconus).  (For more information on this disorder, choose "Beals
Syndrome" as your search term in the Rare Disease Database).

Cohen Syndrome is a rare genetic disorder characterized by multiple
facial, mouth, and eye abnormalities.  There is muscle weakness, obesity and
mental retardation.  Generally there is low birth weight, an unusually small
head and prominent lips.  Other characteristics of Cohen Syndrome may include
narrow hands and feet with long fingers and toes and the ability to extend
the joints beyond their normal range (hyperextensitivity).  There may be
deformities of the knees, elbow and spine as well as a slight curvature to
the spine (scoliosis).  (For more information on this disorder, choose "Cohen
Syndrome" as your search term in the Rare Disease Database).

Therapies:  Standard

All Marfan Syndrome patients should avoid sports, heavy lifting and any
exercise that increases the strain on the aorta produced by vigorous beating
of the heart.  Beta-adrenergic blocking drugs such as propranolol and
atenolol have proven useful in treating the cardiovascular symptoms.  Both
drugs help to reduce the strength and frequency of the contractions of the
heart.  In doing so, they may reduce the strain on the aorta.  Beta-blockers
generally produce few side effects and may delay, or possibly prevent the
need for heart surgery.  The dosage needs to be adjusted to the individual
patients needs, and therapy should be closely monitored.  However, surgical
replacement of the aorta may eventually become necessary.

In the skeletal system, scoliosis and deformity of the chest may
represent a serious problem for people with Marfan Syndrome.  Curvatures of
the spine of more than 10 degrees should be referred to an orthopedic surgeon
for correct management.  Some children have been treated with hormones such
as estrogen to accelerate the growth cycle and the onset of puberty.  This
reduces the number of years during which the spine is the most susceptible to
deformity.  Hormonal treatment has been most effective in females.  Although
medical side effects are generally minimal and adult height may be reduced by
this treatment, the child must deal with the social and psychologic
difficulties of becoming sexually mature before his or her peers.

Deformities of the sternum in patients with Marfan Syndrome (both
protruding and inverted breast deformities) may be corrected surgically.
Repair of a chest deformity is best delayed until mid-adolescence at the
earliest.

The eyes require careful attention from early childhood.  Failure to
detect any of the several abnormalities that can affect the eyes may result
in a dimness of vision and other visual impairment.  Increased risk of
retinal detachment does demand special attention.  The eyes should receive
special protection from injury during work or sports.  Sports that may
involve trauma to the head, such as football, boxing, and diving, should be
avoided.

Every person with Marfan Syndrome should have a yearly electrocardiogram
to check the size and function of the heart and aorta.  Impaired functioning
of the heart valves may respond to various cardiac medications.  However,
surgical replacement with an artificial valve may become necessary.

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

Therapies:  Investigational

Other beta-adrenergic blocking drugs are being investigated as possible
therapies for the cardiovascular symptoms of Marfan Syndrome.  Basic research
is being conducted on the cause of Marfan Syndrome, including studies of the
biochemistry of connective tissue.  Scientists are also studying the nature
of the genetic defect that causes this disorder.

Clinical trials are underway to study all patients with a diagnosis of
Marfan Syndrome who are 25 years of age or younger.  Interested persons may
wish to contact:

     Dr. Bruce S. Alpert
     University of Tennessee, Division of Cardiology
     848 Adams Ave.
     Memphis, TN  38103
     [phone]

to see if further patients are needed for this research.

Research on birth defects 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 disorders in the future.

This disease entry is based upon medical information available through
September 1992.  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 Marfan Syndrome, please contact:

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

     The National Arthritis and Musculoskeletal and Skin Diseases Information
Clearinghouse
     Box AMS
     Bethesda, MD  20892
     [phone]

     National Marfan Foundation
     382 Main Street
     Port Washington, New York, NY 11050
     [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, 10th Ed.:  Victor A. McKusick, Editor:  Johns
Hopkins University Press, 1992.   Pp. 696-698.

THE METABOLIC BASIS OF INHERITED DISEASE, 6th Ed.:  Charles R. Scriver, et
al., Editors; McGraw Hill, 1989.  Pp. 2833-2834.

INTERNAL MEDICINE, 2nd Ed.:  Jay H. Stein, Editor-In-Chief; Little, Brown
and Co., 1987.  Pp. 1361.

CECIL TEXTBOOK OF MEDICINE, 19th Ed.:  James B. Wyngaarden, and Lloyd H.
Smith, Jr., Editors; W.B. Saunders Co., 1990.  Pp. 1122-1123.

BIRTH DEFECTS ENCYCLOPEDIA, Mary Louise Buyse, M.D., Editor-In-Chief;
Blackwell Scientific Publications, 1990.  Pp. 1104-1105.

MARFAN SYNDROME.  WHAT YOU NEED TO KNOW, E.M. Woerner et al.; Postgrad
Med (April 1990; 87(5)):  Pp. 229-236.

THE MARFAN SYNDROME, R.E. Pyeritz; Am Fam Physician (Dec 1986; 34(6)) Pp.
83-94.