Family: Education: Descriptions of Disorders
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APERT SYNDROME
APERT SYNDROME
What Is Apert Syndrome?
Apert syndrome is a type of birth defect that occurs in about 1 of every 100,000
to 160,000 births. Infants with Apert syndrome are born with abnormalities of
the face, skull, hands, and feet. This condition was first recognized by, and
is named for, a doctor named Frederick Apert, who studied the condition in several
children in 1942.
Craniosynostosis
Perhaps the most notable feature of Apert syndrome is the abnormal skull
shape, which is due to craniosynostosis. This is a group of conditions
that affect the bones of the skull, which normally are separated by a narrow
space at birth. At the edges of this narrow space, or suture, special
cells grow during the first few years of life, causing the bones to fuse together.
In craniosynostosis, the sutures close too early. The growing brain then exerts
pressure on the rigid skull bones, which cannot expand properly to accommodate
it. Like a balloon being pinched on one side as it is being blown up, the
skull grows abnormally to make room for the brain. (See Craniosynostosis
for more information about this disorder.)
The type of craniosynostosis seen in children with Apert syndrome is called
brachycephaly. In this condition, the coronal suture closes too
early. The coronal suture runs along the top front of the head, normally separating
the bones of the forehead and the top of the head. Fusion of this suture keeps
the skull from expanding front to back, and the result is a head shape that
is flattened in this direction. This abnormality in turn affects the bones of
the middle of the face, which is flattened as a result.
Hand and Foot Abnormalities
In addition to craniosynostosis, children with Apert syndrome have fused or
webbed fingers and toes. Usually three or four of the fingers on each hand and
all five toes on each foot are fused together to various degrees. Five distinct
fingernails and toenails may be present, or they too may be connected across
the digits. As the child grows, the bones of the hand and feet gradually become
fused together, causing the fingers and toes to become stiff and difficult to
move. With time, this gradual fusion may also affect the shoulders, elbows,
hips, and knees. Children with Apert usually are shorter as adults, partly because
of shortened lower limbs.
Other Abnormalities
Up to about 10% of children with Apert syndrome also have abnormalities of
certain internal organs. These problems may include heart defects and abnormalities
of the gastrointestinal tract, trachea (windpipe), uterus, and brain. Some children
with Apert syndrome also have other abnormalities, such as the following:
- Visual problems due to an imbalance in the muscles that move the eyes
- Hearing loss due to frequent ear infections
- Severe acne
- Mild mental retardation
What Causes Apert Syndrome?
Apert syndrome is usually caused by a mutation, or change, in a gene known
as the fibroblast growth factor receptor gene (designated the FGFR2 gene). Everyone
has two copies of this gene, one from each parent. Like all genes, the FGFR2
gene is made up of thousands of chemical building blocks that make up a person’s
DNA. In Apert syndrome, a single one of these building blocks in one of the
genes has changed. The other copy of the gene is normal.
This one tiny change in one of the genes is responsible for the features of
Apert syndrome.
The FGFR2 gene mutation that causes Apert syndrome may be passed on
from a parent, but in most cases it arises spontaneously. Spontaneous mutations
normally occur during cell division as the fetus grows. The vast majority of
these mutations are harmless, but some are the cause of problems such as Apert
syndrome. Older age of the father has been linked to spontaneous mutations causing
Apert syndrome. In rare cases, one parent may carry the genetic mutation in
an egg or sperm cell, without having the disorder themselves, and pass the defect
on to their children. A parent who does have Apert syndrome has a 50% chance
of passing down the disorder to his or her children.
The craniosynostosis of Apert syndrome develops in a slightly different way
than other craniosynostosis syndromes. A baby with Apert syndrome typically
has closed coronal sutures at birth. In addition, instead of the normal skull
sutures that lie along the top of the head, there is an open gap that runs from
the forehead to the posterior fontanel (the small space that is normally
present at the crown of a baby’s head and that fuses together in the first years
of life). Unlike a normal skull suture, this abnormal gap does not contain any
of the cells at its edges that normally cause the sutures to close. Instead,
the gap fills in with small islands of bone over the first 2–3 years of life,
until the defect is closed. At that point, there is no more room for skull growth.
The type of craniosynostosis that results is called functional craniosynostosis.
How Is Apert Syndrome Diagnosed?
Apert syndrome is diagnosed by clinical examination. The presence of brachycephalic
craniosynostosis, together with fused fingers and toes, together confirm the
diagnosis. Because it is known what type of gene defect causes the condition,
it is possible to confirm the diagnosis through genetic testing. However, this
is usually not necessary after birth. If Apert syndrome is suspected in the
fetus during pregnancy, genetic testing can be done to confirm the diagnosis.
How Is Apert Syndrome Treated?
Surgery is used to repair the abnormalities of Apert syndrome. Most patients
require numerous operations over several years. The features of the skull and
face are typically addressed first. Additional surgery may be done to improve
the upper airway, which may be partly blocked; to correct severe eye problems;
or to address dental problems.
Multiple operations may also be needed to improve the function and appearance
of the hands and, to a lesser degree, the feet. Many patients require multiple
operations into their adolescence and early adulthood.
Resources
Support Groups
The Craniofacial Support Group provides support and information to families
and individuals with craniosynostosis.
Craniofacial Support Group
44 Helmsdale Road
Leamington Spa CV32 7DW
United Kingdom
44 1 (926) 33-4629
E-mail: SteveMoody@headlines.org.uk
Web site: headlines.org.uk
MUMS: National Parent-to-Parent Organization uses a database of over
14,000 families from 45 countries covering more than 2500 disorders to match
and connect parents with other parents whose children have the same or a similar
condition.
MUMS
c/o Julie Gordon
150 Custer Court
Green Bay, WI 54301-1243
(877) 336-5333
Web site: www.netnet.net/mums
The Apert Support & Information Network was begun by Christine Clark,
whose daughter was born with Apert syndrome. The organization publishes a newsletter,
Apert News, maintains a networking list for families all over the world,
and provides phone support.
Apert Support & Information Network
PO Box 1184
Fair Oaks, CA 95628
(916) 961-1092 (phone & fax)
Web site: www.apert.org
E-mail: www.apertnet@ix.netcom.com
On the Web
FACES: The National Craniofacial Association assists children and adults
with craniofacial disorders resulting from disease, accident, or birth, providing
general information, contact with other families, and other helpful resources.
FACES
P. O. Box 11082
Chattanooga, TN 37401
1-800-3-FACES-3
Web site: www.faces-cranio.org
E-mail: faces@faces-cranio.org
Reading Matter
Children with Facial Differences: A Parent’s Guide (written by Hope
Charkins, MSW, and published by Woodbine House, 1996) is an excellent resource
for help in coping with the medical, emotional, social, educational, legal,
and financial challenges presented by the facial differences of one’s children.
Author: Deborah J. Shuman
Date: November 1, 2000
Disclaimer: Links to support groups and relevant web sites do not signify
an endorsement.
© 2000 The Johns Hopkins University
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Last Updated:
12/16/03
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