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Dystrophic Type, Click Here
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The
following description of Epidermolysis Bullosa was taken from the NIAMS website. Thank You!
Questions and Answers about Epidermolysis
Bullosa
This information is for people who have epidermolysis bullosa
(ep-ee-der-MOL-eh-sis bull-O-sa, often called "EB"), parents and
caregivers of children with EB, and others interested in learning more
about the disease. The information herein describes the disease and its symptoms
and contains information about diagnosis and treatment, as well as
current research efforts supported by the National Institute of
Arthritis and Musculoskeletal and Skin Diseases (NIAMS) and other
components of the Department of Health and Human Services' National
Institutes of Health (NIH). It also discusses issues such as skin care
and quality of life for people with EB. If you have questions after
reading this, you may wish to discuss them with your doctor or a
dermatologist (a specialist in treating skin conditions).
What Is Epidermolysis Bullosa?
EB is a group of blistering skin conditions. The skin is
so fragile in people with EB that even minor rubbing may cause
blistering. At times, the person with EB may not be aware of rubbing or
injuring the skin even though blisters develop. In severe EB, blisters
are not confined to the outer skin. They may develop inside the body, in
such places as the linings of the mouth, esophagus, stomach, intestines,
upper airway, bladder, and the genitals.
The skin has an outer layer called the epidermis and an
underlying layer called the dermis. The place where the two layers meet
is called the basement membrane zone. (See the diagram of the skin
below.) The main forms of EB are EB Simplex, Junctional EB, and
Dystrophic EB. EB Simplex occurs in the outer layer of skin; Junctional
EB and Dystrophic EB occur in the basement membrane zone. These major
types of EB, which will be described throughout this text, also have
many subtypes.
Who Gets Epidermolysis Bullosa?
It is estimated that 2 to 4 out of every 100,000 people,
or up to 12,000 people in the United States, have some form of EB. It
occurs in all racial and ethnic groups and affects males and females
equally. The disease is not always evident at birth. Milder cases of EB
may become apparent when a child crawls, walks, or runs, or when a young
adult engages in vigorous physical activity.
What Causes Epidermolysis Bullosa?
Most people with EB have inherited the condition through
faulty genes they receive from one or both parents. Genes are located in
the body's cells and determine inherited traits passed from parent to
child. They also govern every body function, such as the formation of
proteins in the skin. More than 10 genes are known to underlie the
different forms of EB. Genes are located on chromosomes, which are
structures in each cell's nucleus.
In an autosomal dominant form of EB, the disease gene is
inherited from only one parent who has the disease, and there is a 50
percent (1 in 2) chance with each pregnancy that a baby will have EB. In
the autosomal recessive form, the disease gene is inherited from both
parents. Neither parent has to show signs of the disease; they simply
need to "carry" the gene, and there is a 25 percent (1 in 4) chance with
each pregnancy that a baby will have EB. EB can also be acquired through
a mutation (abnormal change) in a gene that occurred during the
formation of the egg or sperm reproductive cell in a parent. Neither the
sex of the child nor the order of birth determines which child or how
many children will develop EB in a family that has the faulty gene.
Although EB Simplex can occur when there is no evidence of
the disease in the parents, it is usually inherited as an autosomal
dominant disease. In EB Simplex, the faulty genes are those that provide
instructions for producing keratin, a fibrous protein in the top layer
of skin. As a result, the skin splits in the epidermis, producing a
blister.
In Junctional EB, there is a defect in the genes inherited
from both parents (autosomal recessive) that normally promote the
formation of anchoring filaments (thread-like fibers) or hemidesmosomes
[hem-ee-DES-mo-soms] (complex structures composed of many proteins).
These structures anchor the epidermis to the underlying basement
membrane. The defect leads to tissue separation and blistering in the
upper part of the basement membrane.
There are both dominant and recessive forms of Dystrophic
EB. In this condition, the filaments that anchor the epidermis to the
underlying dermis are either absent or do not function. This is due to
defects in the gene for type VII collagen, a fibrous protein that is the
main component of the anchoring filaments.
Epidermolysis bullosa acquisita
(EBA) is a rare autoimmune
disorder where the body attacks its own anchoring fibrils with
antibodies, the special proteins that help fight and destroy foreign
substances that invade the body. In a few cases, it has occurred
following drug therapy for another condition; in most cases, the cause
is unknown.
How Is Epidermolysis Bullosa Diagnosed?
Dermatologists can identify where the skin is separating
to form blisters and what kind of EB a person has by doing a skin biopsy
(taking a small sample of skin that is examined under a microscope). One
diagnostic test involves use of a microscope and reflected light to see
if proteins needed for forming connecting fibrils, filaments, or
hemidesmosomes are missing or reduced in number. Another test involves
use of a high-power electron microscope, which can greatly magnify
tissue images, to identify structural defects in the skin.
Recent techniques make it possible to identify defective
genes in EB patients and their family members. Prenatal diagnosis can
now be accomplished by amniocentesis (removing and examining a small
amount of amniotic fluid surrounding the fetus in the womb of a pregnant
woman) or sampling the chorionic villus (part of the outer membrane
surrounding the fetus) as early as the tenth week of pregnancy.
What Are the Symptoms of Epidermolysis Bullosa?
The major sign of all forms of EB is fragile skin that
blisters, which can lead to serious complications. For example,
blistering areas may become infected, and blisters in the mouth or parts
of the gastrointestinal tract may interfere with proper nutrition.
Following is a summary of some of the characteristic signs
of various forms of EB.
-
EB Simplex (EBS)--A generalized form of
EBS usually begins with blistering that is evident at birth or shortly
afterward. In a localized, mild form called Weber-Cockayne, blisters
rarely extend beyond the feet and hands. In some subtypes of EBS, the
blisters occur over widespread areas of the body. Other signs may
include thickened skin on the palms of the hands and soles of the
feet; rough, thickened, or absent fingernails or toenails; and
blistering of the soft tissues inside the mouth. Less common signs
include growth retardation; blisters in the esophagus; anemia (a
reduction in the red blood cells that carry oxygen to all parts of the
body); scarring of the skin; and milia, which are small white skin
cysts.
-
Junctional EB (JEB)--This disease is
usually severe. In the most serious forms, large, ulcerated blisters
on the face, trunk, and legs can be life-threatening due to
complicated infections and loss of body fluid that leads to severe
dehydration. Survival is also threatened by blisters that affect the
esophagus, upper airway, stomach, intestines, and the urogenital
system. Other signs found in both severe and mild forms of JEB include
rough and thickened or absent fingernails and toenails; a thin
appearance to the skin (called atrophic scarring); blisters on the
scalp or loss of hair with scarring (scarring alopecia); malnutrition
and anemia; growth retardation; involvement of soft tissue inside the
mouth and nose; and poorly formed tooth enamel.
-
Dystrophic EB (DEB)--The dominant and
recessive inherited forms of DEB have slightly different symptoms. In
some dominant and mild recessive forms, blisters may appear only on
the hands, feet, elbows, and knees; nails usually are shaped
differently; milia may appear on the skin of the trunk and limbs; and
there may be involvement of the soft tissues, especially the
esophagus. The more severe recessive form is characterized by blisters
over large body surfaces, loss of nails or rough or thick nails,
atrophic scarring, milia, itching, anemia, and growth retardation.
Severe forms of recessive DEB also may lead to severe eye inflammation
with erosion of the cornea (clear covering over the front of the eye),
early loss of teeth due to tooth decay, and blistering and scarring
inside the mouth and gastrointestinal tract. In most people with this
form of EB, some or all the fingers or toes may fuse
(pseudosyndactyly). Also, individuals with recessive DEB have a high
risk of developing a form of skin cancer called squamous cell
carcinoma. It primarily occurs on the hands and feet. The cancer may
begin as early as the teenage years. It tends to grow and spread
faster in people with EB than in those without the
disease.
How Is Epidermolysis Bullosa Treated?
Persons with mild forms of EB may not require extensive
treatment. However, they should attempt to keep blisters from forming
and prevent infection when blisters occur. Individuals with moderate and
severe forms may have many complications and require psychological
support along with attention to the care and protection of the skin and
soft tissues. Patients, parents, or other care providers should not feel
that they must tackle all the complicated aspects of EB care alone.
There are doctors, nurses, social workers, clergy members,
psychologists, dietitians, and patient and parent support groups that
can assist with care and provide information and emotional support.
Preventing Blisters
In many forms of EB, blisters will form with the slightest
pressure or friction. This may make parents hesitant to pick up and
cuddle young babies. However, a baby needs to feel a gentle human touch
and affection, and can be picked up when placed on a soft material and
supported under the buttocks (bottom) and behind the neck. A baby with
EB should never be picked up under the arms.
A number of things can be done to protect the skin from
injury. These include:
- avoiding overheating by keeping rooms at an even temperature
- applying lubricants to the skin to reduce friction and keep the
skin moist
- using simple, soft clothing that requires minimal handling when
dressing a child
- using sheepskin on car seats and other hard surfaces
- wearing mittens at bedtime to help prevent scratching
Caring for Blistered Skin
When blisters appear, the objectives of care are to reduce
pain or discomfort, prevent excessive loss of body fluid, promote
healing, and prevent infection.
The doctor may prescribe a mild analgesic to prevent
discomfort during changes of dressings (bandages). Dressings that are
sticking to the skin may be removed by soaking them off in warm water.
While daily cleansing may include a bath with mild soaps, it may be more
comfortable to bathe in stages where small areas are cleaned at a
time.
Blisters can become quite large and create a large wound
when they break. Therefore, a medical professional will likely provide
instructions on how to safely break a blister in its early stages while
still leaving the top skin intact to cover the underlying reddened area.
One technique is to pat the blister with an alcohol pad before popping
it at the sides with a sterile needle or other sterile tool. The fluid
can then drain into a sterile gauze that is used to dab the blister.
After opening and draining, the doctor may suggest that an antibiotic
ointment be applied to the area of the blister before covering it with a
sterile, non-sticking bandage. To prevent irritation of the skin from
tape, a bandage can be secured with a strip of gauze that is tied around
it. In milder cases of EB or where areas are difficult to keep covered,
the doctor may recommend leaving a punctured blister open to the
air.
A moderately moist environment promotes healing, but heavy
drainage from blister areas may further irritate the skin, and an
absorbent or foam dressing may be needed. There are also contact layer
dressings where a mesh layer through which drainage can pass is placed
on the wound and is topped by an outer absorbent layer. The doctor or
other health care professional may recommend gauze or bandages that are
soaked with petroleum jelly, glycerin, or moisturizing substances, or
may suggest more extensive wound care bandages or products.
Treating Infection
The chances of skin infection can be reduced by good
nutrition, which builds the body's defenses and promotes healing, and by
careful skin care with clean hands and use of sterile materials. For
added protection, the doctor may recommend antibiotic ointments and
soaks.
Even in the presence of good care, it is possible for
infection to develop. Signs of infection are redness and heat around an
open area of skin, pus or a yellow drainage, excessive crusting on the
wound surface, a red line or streak under the skin that spreads away
from the blistered area, a wound that does not heal, and/or fever or
chills. The doctor may prescribe a specific soaking solution, an
antibiotic ointment, or an oral antibiotic to reduce the growth of
bacteria. Wounds that are not healing may be treated by a special wound
covering or biologically developed skin.
Treating Nutritional Problems
Blisters that form in the mouth and esophagus in some
people with EB are likely to cause difficulty in chewing and swallowing
food and drinks. If breast or bottle feeding results in blisters,
infants may be fed using a preemie nipple (a soft nipple with large
holes), a cleft palate nipple, an eyedropper, or a syringe. When the
baby is old enough to take in food, adding extra liquid to pureed
(finely mashed) food makes it easier to swallow. Soups, milk drinks,
mashed potatoes, custards, and puddings can be given to young children.
However, food should never be served too hot.
Dietitians are important members of the health care team
that assists people with EB. They can work with family members and older
patients to find recipes and prepare food that is nutritious and easy to
consume. For example, they can identify high-caloric and
protein-fortified foods and beverages that help replace protein lost in
the fluid from draining blisters. They can suggest vitamin and mineral
nutritional supplements that may be needed, and show how to mix these
into the food and drinks of young children. Dietitians can also
recommend adjustments in the diet to prevent gastrointestinal problems,
such as constipation, diarrhea, or painful elimination.
Surgical Treatment
Surgical treatment may be necessary in some forms of EB.
Individuals with the severe forms of autosomal recessive Dystrophic EB
whose esophagus has been narrowed by scarring may require dilation of
their esophagus for food to travel from the mouth to the stomach. Other
individuals who are not getting proper nutrition may need a feeding tube
that permits delivery of food directly to the stomach. Also, patients
whose fingers or toes are fused together may require surgery to release
them.
What Is the Value of Genetic Counseling?
Epidermolysis Bullosa is a difficult, sometimes painful,
and often disfiguring disease. Most adults with signs of EB or who know
they carry the gene would like to spare future generations, including
their own potential offspring, from this condition. With the knowledge
of specific gene mutations that cause EB, it is now possible to
determine the specific gene mutation in the family and then to conduct
prenatal tests on pregnant women with a fetus at risk of EB to determine
the status of the fetus. Specific laboratories, such as the one
affiliated with the Dystrophic Epidermolysis Bullosa Research
Association (DebRA), can test for gene mutations. Also, a genetic counselor can provide
information on the likelihood of passing the gene for EB to children and
provide advice on future childbearing. Genetic counseling can be a
crucial step in helping families make decisions about their family
planning.
What Research Is Being Conducted on Epidermolysis
Bullosa?
At one time, research on EB was limited to describing the
disease and understanding what happens in the layers of skin. Today,
research focuses upon finding gene mutations and their effect on the
tissues, copying genes, reproducing gene mutations for research to
correct them, inserting healthy genes to replace missing or mutated
genes, and screening those who may have a gene mutation causing EB.
Some researchers are aiming their sights on future gene
therapy. They are developing mouse models to detect the involvement of
different tissues in EB and to test the delivery of modified cells to
genetically altered mice that have EB traits. While scientists have
already been able to achieve genetic correction of some human genetic
skin diseases, they have not been able to sustain the results beyond a
few weeks or months. Therefore, they are working to achieve long-lasting
corrective gene delivery that can be used as a springboard for further
gene therapy trials in humans.
In Dystrophic EB, the fibrils that anchor the epidermis to
the underlying dermis are either absent or do not function well.
Scientists are introducing a gene for absent collagen (type VII) into
cultured keratinocytes and fibroblasts (types of skin cells) obtained
from patients whose cells cannot make the protein. It is hoped that the
gene-corrected cells eventually can be transplanted back into the
patients to promote and sustain the formation of anchoring fibrils.
Applying newer diagnostic techniques, investigators are
beginning to link specific gene defects with the protein problems they
produce. Now that the EB-causing gene mutations can be identified, there
is a way that ova (eggs) that do not contain an abnormal gene can be
selected for in vitro fertilization outside the body, thus improving the
chances of having healthy children in families with the EB gene.
Researchers are also assessing the effectiveness of using
proteins called cytokines and new kinds of dressings to heal blister
wounds.
~ ~ ~
Looking for
information on the latest Research to cure EB
at Stanford? Click
Here
You can see descriptions of Current Funded Research and European Union Funded Research at this website:
http://www.debra-international.org/research3.htm
