Familial Dysautononmia (FD)
Familial Dysautonomia (FD) is an inherited disorder,
a rare genetic disease that results from the abnormal development
of the nervous system, particularly the sensory and autonomic
systems. The autonomic nervous system controls such involuntary
functions such as swallowing, digestion, temperature and blood
pressure regulation.
· Symptoms
and Detection
· Life
Expectancy
· Testing
and Diagnosis
· Treatment
· Incidence
and Carriers
· Premarital
and Prenatal Screening
· Resources
and More
· Dysautonomia
Treatment and Evaluation Centers
IMPORTANT
NEW INFORMATION
An excerpt from the New York Based Jewish paper, the Forward
---- (August, 2001)
Race To Discover Gene
Mutation Ends in a Virtual Tie
Massachusetts General, Fordham University Share Credit for Dysautonomia Advance
By MIRIAM TAUBER
In a remarkable confluence of scientific sleuthing, two medical teams, working
independently, discovered the gene mutation that causes familial dysautonomia
within days of each other this past December.
The teams, which are based respectively at Fordham University in New York and Massachusetts General Hospital in Boston, published their finding in the March issue of the American Journal of Human Genetics.
The discovery of the FD gene means a carrier test for the fatal recessive genetic disorder can be offered to the population in which the disease is most prevalent: Ashkenazi Jews. The Massachusetts General medical team and the Dysautonomia Foundation offer testing at New York University Medical Center, New York's Mount Sinai Hospital and Hadassah Hospital in Jerusalem. The Fordham team will be making carrier testing available at Albert Einstein Medical Center in the Bronx.
Symptoms
The usual function of the problematic gene is to produce a substance
called dopamine beta-hydroxylase. A lack of beta-hydroxylase creates
muliple problems
One of the most striking manifestations is the absence of overflow
of tears with emotional crying. Though, keep in mind, it can be
normal for a child not to have tears the first seven months of
life. Severe eye problems are common because of the resulting
dry eye and the absence of corneal response to foreign objects
in the eye. Other signs of the disorder can be present from birth
such as a high prevalence of breech presentation, weak or absent
sucking ability, and poor tone.
Additional indicators include difficulties with swallowing, temperature
regulation, blood pressure regulation, and feeding. Individuals
with FD also suffer from seizures, are vulnerable to pneumonia,
suffer from spine curvature (in 90% by age 13).
Approximately 40% of patients will have what is termed Dysautonomia
Crisis. That is a group of symptoms in reaction to stress. In
addition to vomiting, there is frequently increased heart rate
and blood pressure, sweating, and a negative change in personality.
· Decreased response
to pain and temperature
· Orthostatic hypotension
(blood pressure drops when changing position i.e. standing up)
· Delayed developmental
milestones
· Speech and motor
incoordination
· Unsteady gait
· Labile blood pressure
(fluctuating BP)
· Corneal anesthesia
· Marked sweating with
excitement, eating or the first stage of sleep
· Breath-holding episodes
· Poor growth
Life
Expectancy
In general Familial Dysautonomia is a fatal disease, with approx 50% of individuals
reaching the age of Thirty. Yet individuals affected by FD are usually of normal
intelligence, and can be expected to function independently if treatment is
begun early and major disabilities avoided
Incidence and Carriers
Testing
and Diagnosis
The following test
determine the diagnosis of FD
· The lack of fungiform papillae
on the tongue,
· The lack of flare after intradermal
histamine test
· Greatly diminished deep tendon
reflexes.
· No overflow tears with emotional
crying
Treatment
Treatment has had a dramatic impact on improving the prognosis of FD. Prior
to 1960, approximately fifty percent of patients died before reaching the age
of five. Nowadays, about half of the patients live to the age of thirty. The
greatest impact on treatment has been the increased use of gastrostomy (surgical
incision into the stomach) and fundoplication (mobilization of the lower end
of the esophagus and subsequent folding of a portion of the stomach around it)
to avoid aspiration pneumonia and to maintain adequate nutrition and hydration.
As there is still no cure for FD, treatments are symptomatic, as per the following:
· Artificial tears
· Special feeding techniques
· Special therapies (occupational,
physical, speech)
· Special drug management of autonomic
manifestations such as temperature regulation, blood pressure fluctuations,
and digestive problems.
· Respiratory care
· Protecting the child from injury
(coping with decreased taste, temperature and pain perception)
· Treatment of orthopedic problems
(tibial torsion and spinal curvature)
· Compensating for labile blood pressures
Currently research in FD includes developing better treatment of orthostatic
hypotension and better control of centrally induced nausea and vomiting. In
the future, gene therapy may become an option.
Incidence
and Carriers
An estimated one in 30 Ashkenazi Jews is a carrier of FD.
An individual has to inherit a change gene from both parents to have the disease.
If two carriers for Familial Dysautonomia have a child each child has:
· One in Four chance of having Familial
Dysautonomia
· Two in Four chance of being a carrier
· One in Four chance of neither having
having FD nor being a carrier.
· Unaffected siblings of individuals
with FD have a Two in Three chance of being carriers.
Prenatal
Screening
GREAT NEWS!! Until recent events (see above NEW IMPORTANT INFORMATION) in order
for testing to be done, at least one individual in the family has to have been
diagnosed with FD, for the lab to able to interpret the test
result. But now that the FD gene has been discovered, testing is possible for
everyone! Please contact the
Dysautonomia Foundation, Inc. for more information.
Prenatal diagnosis:
If both members of a couple are shown to be carriers by genetic testing, prenatal
diagnosis by amniocentesis (14-17 weeks) or chorionic villus sampling (10-11
weeks) will be possible.
The laboratories at New York University Medical School and Mount Sinai Hospital
in New York City and at the Hadassah Medical Center in Jerusalem, Israel, have
demonstrated their ability to perform these tests with a high-degree of reliability.
For
Genetic Counseling and Screening Resources
– Click Here
More
Information and Resources
Dysautonomia Foundation, Inc.
315 West 39th Street, Ste 701
New York, NY 10018
Telephone: 212-279-1066
Email:
info@familialdysautonomia.org
Website:
http://www.familialdysautonomia.org
Dysautonomia
Genetic Counseling Center at the
Human Genetics Program
NYU School of Medicine
550 First Avenue, MSB 136
New York, NY 10016
tel: 212 263-5746
fax: 212 263-7590
email: elsa.reich@med.nyu.edu
Center
for the Study and Treatment of Jewish Genetic Diseases
at UPMC Health Systems
Contact: Erin O’Rourke, M.S.
Toll Free 800-334-7980
Email: eorourke@helix.hgen.pitt.edu
National Foundation for Jewish Genetic
Diseases Inc.
250 Park Avenue, Suite 1000
New York, NY 10017
Telephone 212-371-1030
Dysautonomia
Treatment and Evaluation Centers
Dysautonomia Center in New York
The Dysautonomia Treatment and Evaluation Center in New York is under the direction
of Dr. Felicia B. Axelrod. The Center was established at New York University
Medical Center in 1969 to provide care to individuals affected with the genetic
disorder Familial Dysautonomia (FD). This is the only Center for FD in the United
States and thus serves as a resource for patients and physicians worldwide in
assessing and treating FD.
Dysautonomia Center in Israel
The Dysautonomia Center in Israel is at Haddassah Hospital, Mt Scopus in Jerusalem,
and is under the direction of Dr. Channa Maayan. The Israeli Center was established
as a collaborative center and is modeled after the New York facility. After
each patient is evaluated in Israel, information is sent to Dr. Axelrod for
review.