home
***
CD-ROM
|
disk
|
FTP
|
other
***
search
/
CD-ROM Today 1996 January
/
CD-ROM Today 1996 January.iso
/
dp
/
0429
/
04292.txt
< prev
next >
Wrap
Text File
|
1994-01-17
|
6KB
|
163 lines
$Unique_ID{BRK04292}
$Pretitle{}
$Title{Trisomy 18 Syndrome}
$Subject{Trisomy 18 Syndrome Trisomy 18 Edward's Syndrome Trisomy E Trisomy
16-18 }
$Volume{}
$Log{}
Copyright (C) 1986, 1992 National Organization for Rare Disorders, Inc.
217:
Trisomy 18 Syndrome
** IMPORTANT **
It is possible the main title of the Article (Trisomy 18 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
Trisomy 18
Edward's Syndrome
Trisomy E
Trisomy 16-18
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.
Trisomy 18 Syndrome is a genetic disorder with onset before birth.
Paternal and maternal age are usually above average. Babies appear thin and
frail. They fail to thrive and have difficulty feeding. These children show
generalized increased muscle tension (hypertonicity) with rigidity in flexion
of the limbs and mental retardation.
Symptoms
The newborn infant with Trisomy 18 is premature or small for its gestational
age, with markedly retarded development (hypoplasia) of skeletal muscle and
subcutaneous fat. The baby's cry is weak, and response to sound is
decreased. There is often a history of feeble fetal activity, excess of
fluid in the fetal sac, a small placenta, and a single umbilical artery.
The back part of the head is prominent; there is a narrow bifrontal
diameter with decreased orbital ridges, short eyelid fissures, a small mouth
and unusually small jaw, all of which give the face a pinched appearance. A
small head (microcephaly), fold of the eyelid in the lateral corner of the
eye (epicanthal folds), low-set malformed ears, and cleft lip and/or palate
are common. The peculiar clenched fist with the index finger overlapping the
3rd and 4th fingers is almost distinctive of this disorder. Absence of the
distal crease on the 5th finger is common as is a low-arch dermal ridge
pattern on the fingertips. The nails are underdeveloped and the big toe is
shortened and frequently bent backward (dorsiflexed). Underdeveloped or
absent thumbs, clubfeet, rocker-bottom feet, and webbed fingers and toes
(syndactyly) may also occur.
An opening in the ventricular septum of the heart (ventricular septal
defect), persistent blood vessel connecting the aorta to the pulmonary artery
(patent ductus arteriosus), an opening in the septum between the two atria in
the heart (atrial septal defect), and abnormalities in the pulmonary and/or
aortic valves may be present. (For more information on these defects, please
see the articles in the Rare Disease Database.)
Congenital anomalies of the lung, diaphragm, kidneys and ureters are
frequent. Hernias and/or separation of the rectus muscles of the abdominal
wall, redundant skin folds especially over the back of the neck, and, in
males, failure of the testes to descend into the scrotum are also common.
Mental retardation in Trisomy 18 Syndrome is usually severe.
Causes
Trisomy 18 Syndrome is caused by the presence of a third chromosome 18. This
chromosome is responsible for the physical and mental abnormalities of this
developmental disorder.
Affected Population
Female infants are affected 3 times greater than male infants with Trisomy 18
Syndrome. Children with this disorder are generally born to older parents.
Therapies: Standard
Treatment of Trisomy 18 Syndrome is symptomatic and supportive. Special
education, physical therapy, and other medical, social, or vocational
services are of benefit to the patient, and are often necessary for the child
to reach his/her full potential.
Therapies: Investigational
This disease entry is based upon medical information available through
February 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 Trisomy 18 Syndrome, please contact:
National Organization for Rare Disorders (NORD)
P.O. Box 8923
New Fairfield, CT 06812-1783
(203) 746-6518
Support Organization for Trisomy 18/13 (SOFT 18/13)
National Headquarters
4625 Lindell Blvd., Suite 501
St. Louis, MO 63108
(314) 367-0055
S.O.F.T. Canada Inc.
1214 Concession 5 West
RR2 Waterdown, Ontario LOR 2H2
(416) 659-3216
NIH/National Institute of Child Health and Human Development
9000 Rockville Pike
Bethesda, MD 20205
(301) 496-5133
Association for Retarded Citizens of the U.S.
P.O. Box 6109
Arlington, TX 76005
(817) 640-0204
(800) 433-5252
Mental Retardation Association of America
211 East 300 South, Suite 212
Salt Lake City, UT 84111
(801) 328-1575
In Touch
10 Norman Road
Sale, Cheshire
M33 3DF
Hants, England
For information on genetics and genetic counseling referrals, please
contact:
March of Dimes Birth Defects Foundation
1275 Mamaroneck Avenue
White Plains, NY 10605
(914) 428-7100
Alliance of Genetic Support Groups
35 Wisconsin Circle, Suite 440
Chevy Chase, MD 20815
(800) 336-GENE
(301) 652-5553
References
SMITH'S RECOGNIZABLE PATTERNS OF HUMAN MALFORMATION, 4th ed., Kenneth L.
Jones, M.D., W.B. Saunders, Co. 1988. Pp. 16-9.