Synonyms

• EB

Disorder Subdivisions

• epidermolysis bullosa simplex
• junctional epidermolysis bullosa
• dystrophic epidermolysis bullosa

Related Disorders List

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

• Herpes Simplex Virus
• Epidermolytic Hyperkeratosis
• Bullous Impetigo
• Incontinetia Pigmenti

General Discussion

Epidermolysis bullosa (EB) is a genetic skin disorder characterized clinically by blister formation from mechanical trauma. There are three main types with additional sub-types identified. There is a spectrum of severity, and within each type, one may be either mildly or severely affected. EB ranges from being a minor inconvenience requiring modification of some activities, to being completely disabling and, in some cases, fatal.



Friction causes blister formation. Blisters can form anywhere on the surface of the skin, within the oral cavity and in more severe forms may also involve the external surface of the eye, as well as the respiratory, gastrointestinal and genitourinary tracts. In some forms of the disease, disfiguring scars and disabling musculoskeletal deformities occur.



Currently, there is no cure for EB. Supportive care includes daily wound care, bandaging, and pain management as needed.

Symptoms

Epidermolysis bullosa is divided into three subdivisions, and each subdivision has subtypes.



Epidermolysis bullosa simplex (EBS) is usually dominantly inherited, and involves disorders of the genes for Keratins 5 and 14 and plectin. Blistering occurs within the uppermost layer of the skin, the epidermis. EBS may be localized to the hands and feet or there may be a generalized distribution, with relatively mild internal involvement. Those with EBS may have thickened calluses on the palms and soles, oral blistering during infancy and rough, thickened fingernails/toenails. EBS does not usually scar.



In junctional epidermolysis bullosa (JEB), is recessively inherited, and involves disorders of the several components of the junction between the epidermis and dermis such as Laminin 332 (previously known as Laminin 5), plectin, and a6b4integrin. There are two major subtypes, Herlitz JEB and JEB- other (includes non-Herlitz JEB, and several other subtypes). Junctional Herlitz EB is a very severe form of EB. Death often occurs during infancy due to overwhelming infection (sepsis), malnutrition, dehydration, electrolyte imbalance or obstructive airway complications. There is a wide spectrum of JEB- O. Oral cavity involvement and irregular pitting of the surfaces of the teeth is common in all subtypes. Infants presenting with pyloric atresia will have trouble with feeding and abdominal distension as neonates and present as surgical emergencies in the newborn period.



Dystrophic epidermolysis bullosa (DEB) can be either dominantly or recessively inherited, and involve defects in Type VII collagen. Blisters occur within the lower layer of the skin. There are two major subtypes, Dominant DEB (DDEB) and Recessive DEB (RDEB).



Dominant dystrophic EB (DDEB): DDEB is usually mild. Blistering may be localized to the hands, feet, elbows and knees or it may be generalized. Common findings include scarring, milia (tiny white bumps), mucous membrane involvement, and abnormal or absent nails. Some family members may only have nail dystrophy.



Recessive dystrophic EB (RDEB): RDEB is typically more generalized and severe than DDEB. In addition to scarring, milia, mucous membrane involvement and nail dystrophy, common manifestations include malnutrition, anemia, esophageal strictures, growth retardation, webbing or fusion of the fingers and toes causing mitten deformity (pseudosyndactyly) with loss of function, development of contractures, malformation of teeth, microstomia and corneal abrasions. Severe generalized RDEB (formerly Hallopeau-Siemens RDEB) tends to the most severe form.

Causes

Inherited epidermolysis bullosa is the focus of this report. The inherited forms follow either autosomal dominant or autosomal recessive inheritance. There is also a rare acquired autoimmune disorder called epidermolysis bullosa aquisita. A mutation in any of several genes encoding the proteins in the epidermis, basement membrane or dermis causes poor integrity of the skin leading to fragility.



Recessive genetic disorders occur when an individual inherits two copies of an abnormal gene for the same trait, one from each parent. If an individual receives one normal gene and one gene for the disease, the person will be a carrier for the disease but usually will not show symptoms. The risk for two carrier parents to both pass the defective gene and have an affected child is 25% with each pregnancy. The risk to have a child who is a carrier like the parents is 50% with each pregnancy. The chance for a child to receive normal genes from both parents and be genetically normal for that particular trait is 25%. The risk is the same for males and females.



All individuals carry 4-5 abnormal genes. Parents who are close relatives (consanguineous) have a higher chance than unrelated parents to both carry the same abnormal gene, which increases the risk to have children with a recessive genetic disorder.



Dominant genetic disorders occur when only a single copy of an abnormal gene is necessary to cause a particular disease. The abnormal gene can be inherited from either parent or can be the result of a new mutation (gene change) in the affected individual. The risk of passing the abnormal gene from affected parent to offspring is 50% for each pregnancy. The risk is the same for males and females.

Affected Populations

Some type of EB occurs in an estimated 1 out of every 50,000 live births. The disorder occurs in every racial and ethnic group throughout the world and affects both sexes equally.

Related Disorders

Any blistering disorder in the new born period may mimic EB. These include herpes simplex virus, epidermolytic hyperkeratosis, bullous impetigo and incontinetia pigmenti.

Standard Therapies

Diagnosis

Diagnosis of the type of EB based on presentation in the neonatal period should be avoided as all types of EB may look alike in this age group. When EB is suspected, a skin biopsy should be obtained and sent to an appropriate laboratory to confirm the diagnosis with transmission electron microscopy (TEM) and/or immunofluorescent antibody/antigen mapping. Molecular genetic testing for mutations in most of the genes known to be associated with the various types of EB is clinically available.



Treatment

By definition, inherited EB is a genetically transmitted disorder characterized by marked fragility of the skin. Any trauma, no matter how minimal it may seem, is likely to cause the skin of an EB child or adult to tear or blister. The following are recommended ways to avoid or minimize this problem:



1. Reducing Friction: Extreme care should be employed in handling the skin of any patient with EB.



2. Non-Adhesive Bandages and Dressings: Adhesive or semi-adhesive dressings, bandages, Band-aids, or tape should not be used on the surface of the skin. Instead, wounds should be covered with an appropriate non-adhesive dressing and then further wrapped loosely with rolled gauze. This can be secured by using a tubular dressing retainer.



3. Keeping the Skin Cool: Nothing hot should ever be applied to the skin of a patient with EB. In particular, bath water should be no warmer than body temperature. Patients should avoid prolonged exposure to ambient heat and humidity. If possible, air conditioned environments should be sought whenever possible.



4. Managing Blisters: Because blisters in EB are not self limiting, and can fill with fluid and grow quite large, they need to be drained.



5. Clothing: In younger children, diapers may require additional padding at the legs and waist. Whenever possible, loose-fitting garments should be worn. If blisters develop from the seams of clothing, garments may be worn inside-out and tags, cuffs and necklines may be removed. Loose fitted, padded shoes are generally better tolerated.



6. Nutritional deficiencies: Many children with EB become anemic due to a chronic loss of blood through wounds, poor nutritional intake and poor absorption of iron. It is important to wok with a Nutritionist experienced in the care of special needs patients. Treatment for iron deficiency anemia is often necessary. Other patients have selenium and carnitine or vitamin D deficiencies which may predispose them to cardiomyopathy and osteoporosis.



7. Monitoring for Cancer: Squamous Cell Carcinoma is the leading cause of death in EB usually occurring after the 2nd decade of life. Patients with Recessive dystrophic EB (RDEB) are at increased risk of developing skin cancers during their lifetimes. It is very important that all EB patients have at least yearly examination of all skin areas.

Investigational Therapies

Stem cell transplant therapy trials for recessive dystrophic epidermolysis bullosa are being conducted at two institutions. For further information contact the following :



University of Minnesota

Center for Translational Medicine

Tim Krepski, RN

612-273-2800

Toll-free: 1-888-601-0787

Email: bmt@umn.ed



Morgan Stanley Children's Hospital

Columbia University Medical Center

Mitchell S Cairo, MD, 212-305-8316, Email: mc1310@columbia.edu

Claire Fanelli, RN, 212-305-2050, Email: cf2370@columbia.edu



Information on current clinical trials is posted on the Internet at www.clinicaltrials.gov. All studies receiving U.S. Government funding, and some supported by private industry, are posted on this government web site.



For information about clinical trials being conducted at the NIH Clinical Center in Bethesda, MD, contact the NIH Patient Recruitment Office:



Tollfree: (800) 411-1222

TTY: (866) 411-1010

Email: prpl@cc.nih.gov



For information about clinical trials sponsored by private sources, contact:

www.centerwatch.com

References

TEXT BOOKS

Fine JD, Hintner H., eds. Life with Epidermolysis Bullosa (EB): Etiology, Diagnosis, Multidisciplinary Care and Therapy, New York: Springer Wien; 2009.



Fine JD, Bauer E, McGuire J , Moshell A, eds.Epidermolysis Bullosa: Clinical, Epidemiologic, and Laboratory Advances and the Findings of the National Epidermolysis Bullosa Registry 1st edition The Johns Hopkins University Press; 1999.



Weston WL, Lane AT, Morelli JG, eds. Color Textbook of Pediatric Dermatology, 4th Edition Mosby/Elsevier, 2007: 348-354.



RECENT REVIEW ARTICLES

Ellen G. Pfendner PhD, Anna Bruckner MD, Paulette Conget PhD, Jemima Mellerio MBBS, Francis Palisson MD, Anne W. Lucky MD Basic science of epidermolysis bullosa and diagnostic and molecular characterization: Proceedings of the IInd International Symposium on Epidermolysis Bullosa. Santiago, Chile, 2005 International Journal of Dermatology 2007 46 (8), 781, 794.



Richard G. Azizkhan MD, Jacqueline E. Denyer RGN, RSCN, RHV, Jemima E. Mellerio BSc, MD, MRCP, Robinson González MD, Magdalena Bacigalupo, Arturo Kantor MD, Gianfranco Passalacqua DDS, Francis Palisson MD, Anne W. Lucky MD Surgical management of epidermolysis bullosa: Proceedings of the IInd International Symposium on Epidermolysis Bullosa, Santiago, Chile, 2005. International Journal of Dermatology 2007 46 (8), 801, 808.



Jemima E. Mellerio BSc, MD, MRCP, Madeline Weiner RNBSN, Jacqueline E. Denyer RGNRSCNRHV, Elizabeth I. Pillay RGNRMRHV, Anne W. Lucky MD, Anna Bruckner MD, Francis Palisson MD (2007) Medical management of epidermolysis bullosa: Proceedings of the IInd International Symposium on Epidermolysis Bullosa, Santiago, Chile, 2005 International Journal of Dermatology 2007 46 (8), 795, 800.



Anne W. Lucky MD, Ellen Pfendner PhD, Elizabeth Pillay RN, Judy Paskel, Madeline Weiner RN, Francis Palisson MD Psychosocial aspects of epidermolysis bullosa: Proceedings of the IInd International Symposium on Epidermolysis Bullosa, Santiago, Chile, 2005 International Journal of Dermatology 2007 46 (8), 809, 814.



FROM THE INTERNET

Epidermolysis Bullosa by Marinkovich, MP Updated: Nov 12, 2008

http://emedicine.medscape.com/article/1062939-overview



Epidermolysis Bullosa Simplex by Pfendner, E, Bruckner, A Updated 8/11/08

http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=gene&part=ebs



Dystrophic Epidermolysis Bullosa by Pfendner, E, Lucky, AW Updated 10/4/07.

http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=gene&part=ebd



Junctional Epidermolysis Bullosa by Pfendner, E, Lucky, AW Posted: 2/22/08.

http://www.ncbi.nlm.nih.gov/bookshelf/br.fcgi?book=gene&part=ebj



Epidermolysis Bullosa with Pyloric Atresia by Pfendner, E, Lucky, AW Posted: 2/22/08

http://www.ncbi

Resources

Dystrophic Epidermolysis Bullosa Research Association of America, Inc. (DEBRA)

40 Rector Street

8th Floor

New York, NY 10006

Tel: (212)868-1573

Fax: (212)868-9296

Tel: (866)332-7276

Email: staff@debra.org

Internet: http://www.debra.org



Coalition for Heritable Disorders of Connective Tissue

4301 Connecticut Avenue, NW, Suite 404

Washington, DC 20008

Tel: (202)362-9599

Fax: (202)966-8553

Tel: (800)778-7171

Email: chdct@pxe.org

Internet: http://www.chdct.org



DebRA

13 Wellington Business Park

Dukes Ride

Crowthorne

Berkshire United Kingdom

., RG45 6LS

.

Tel: +44 1344 771961

Fax: 44 1344 762661

Email: debra@debra.org.uk

Internet: http://www.debra.org.uk



EB Medical Research Foundation

8909 W. Olympic Blvd. #222

Beverly Hills, CA 90211

Tel: (310)854-0957

Email: a.pett@bep-la.com

Internet: http://www.ebkids.org



MUMS National Parent-to-Parent Network

150 Custer Court

Green Bay, WI 54301-1243

USA

Tel: (920)336-5333

Fax: (920)339-0995

Tel: (877)336-5333

Email: mums@netnet.net

Internet: http://www.netnet.net/mums/



Genetic and Rare Diseases (GARD) Information Center

PO Box 8126

Gaithersburg, MD 20898-8126

Tel: (301)251-4925

Fax: (301)251-4911

Tel: (888)205-2311

TDD: (888)205-3223

Email: http://rarediseases.info.nih.gov/GARD/EmailForm.aspx

Internet: http://rarediseases.info.nih.gov/GARD



Madisons Foundation

PO Box 241956

Los Angeles, CA 90024

Tel: (310)264-0826

Fax: (310)264-4766

Email: getinfo@madisonsfoundation.org

Internet: http://www.madisonsfoundation.org



Epidermolysis Bullosa Action Network

16613 Milan De Avila

Tampa, FL 33613

Tel: (813)325-1955

Email: silvia@ebanusa.org

Internet: http://www.ebanusa.org



Australasian Blistering Diseases Foundation

St. George Hospital,

Department of Dermatology

Gray Street

Kogarah

Sydney, NSW 2217

Australia

Tel: 02 9113 2088

Fax: 02 9113 2886

Email: info@blisters.org.au

Internet: http://www.blisters.org.au/BDHome.html



United Survivors with Epidermolysis Bullosa

512 Hillside Circle

Alpine, UT 84004

Tel: (801)319-0160

Email: ebsurvivors@gmail.com