Epidermolysis bullosa simplex
 
[img_r]http://cache.daylife.com/imageserve/0csr2Os1Ff9zA/610x.jpg[/img_r]What is epidermolysis bullosa simplex?

Epidermolysis bullosa is a group of genetic conditions that cause the skin to be very fragile and to blister easily. Erosions and blisters form in response to minor injury or friction, such as rubbing or scratching. Epidermolysis bullosa simplex (EBS) is one of the major forms of epidermolysis bullosa. The signs and symptoms of this condition vary widely among affected individuals. Blistering may primarily affect the hands and feet in mild cases, and the blisters usually heal without leaving scars. Severe cases of this condition involve widespread blistering that can lead to infections, dehydration, and other medical problems. Severe cases may be life-threatening in infancy.

Researchers have identified four major types of epidermolysis bullosa simplex. Although the types differ in severity, their features overlap significantly, and they are caused by mutations in the same genes. Most researchers now consider the major forms of this condition to be part of a single disorder with a range of signs and symptoms.

The mildest form of epidermolysis bullosa simplex, known as the Weber-Cockayne type, is characterized by skin blistering that begins anytime between childhood and adulthood and is usually confined to the hands and feet. Later in life, skin on the palms and soles of the feet may thicken and harden (hyperkeratosis). In the Koebner type, blisters appear at birth or in early infancy and are more widespread. Another form of the disorder, called epidermolysis bullosa simplex with mottled pigmentation, is characterized by patches of darker skin on the trunk, arms, and legs that fade in adulthood. This form of the disorder also involves skin blistering from early infancy, hyperkeratosis of the palms and soles, and abnormal nail growth. The Dowling-Meara type is the most severe form of epidermolysis bullosa simplex. Extensive, severe blistering can occur anywhere on the body, including the inside of the mouth, and blisters may appear in clusters. Blistering is present from birth and tends to improve with age. Affected individuals also experience abnormal nail growth and hyperkeratosis of the palms and soles.

Researchers have identified another skin condition characteristic of epidermolysis bullosa simplex, which they call Ogna type. It is caused by mutations in a gene that is not associated with the other types of epidermolysis bullosa simplex. It is unclear whether Ogna type is a subtype of epidermolysis bullosa simplex or represents a separate form of epidermolysis bullosa.

How common is epidermolysis bullosa simplex?

The exact prevalence of epidermolysis bullosa simplex is unknown, but this condition is estimated to affect 1 in 30,000 to 50,000 people. The Weber-Cockayne type is the most common form of the condition.

What genes are related to epidermolysis bullosa simplex?

Mutations in the KRT5 and KRT14 genes are responsible for the four major types of epidermolysis bullosa simplex. These genes provide instructions for making proteins called keratin 5 and keratin 14. These tough, fibrous proteins work together to provide strength and resiliency to the outer layer of the skin (the epidermis). Mutations in either the KRT5 or KRT14 gene cause cells in the epidermis to become fragile and easily damaged. As a result, the skin is less resistant to friction and minor trauma and blisters easily.

In rare cases of epidermolysis bullosa simplex, no KRT5 or KRT14 gene mutations have been identified. Mutations in another gene, PLEC, have been associated with the uncommon Ogna type of the condition. The PLEC gene provides instructions for making a protein called plectin, which helps attach the epidermis to underlying layers of skin. Researchers continue to search for PLEC gene mutations in people with epidermolysis bullosa simplex. They are also working to determine how these mutations lead to the major features of the condition.

Related Gene(s)

KRT14
KRT5
PLEC

How do people inherit epidermolysis bullosa simplex?

Epidermolysis bullosa simplex is usually inherited in an autosomal dominant pattern, which means one copy of the altered gene in each cell is sufficient to cause the disorder. Some affected people inherit the mutation from one affected parent. Other cases result from new mutations in the gene and occur in people with no history of the disorder in their family.
In rare cases, epidermolysis bullosa simplex is inherited in an autosomal recessive pattern. Autosomal recessive inheritance means the condition results when two copies of the gene in each cell are altered. The parents of an individual with an autosomal recessive disorder typically each carry one copy of the altered gene, but do not show signs and symptoms of the disorder.

Where can I find information about diagnosis, management, or treatment of epidermolysis bullosa simplex?

These resources address the diagnosis or management of epidermolysis bullosa simplex and may include treatment providers.

Gene Review: Epidermolysis Bullosa Simplex (http://www.ncbi.nlm.nih.gov/ bookshelf/ br.fcgi? book= gene& part= ebs)
Gene Tests: Epidermolysis Bullosa Simplex (http://www.ncbi.nlm.nih.gov/ sites/ GeneTests/ lab/ clinical_ disease_ id/ 53753)
MedlinePlus Encyclopedia: Epidermolysis bullosa (http://www.nlm.nih.gov/ medlineplus/ ency/ article/ 001457.htm)

You might also find information on the diagnosis or management of epidermolysis bullosa simplex in Educational resources (http://ghr.nlm.nih.gov/ condition/ epidermolysis- bullosa- simplex/ show/ Educational+ resources) and Patient support (http://ghr.nlm.nih.gov/ condition/ epidermolysis- bullosa- simplex/ show/ Patient+ support).

To locate a healthcare provider, see How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/ handbook/ consult/ findingprofessional) in the Handbook.

Where can I find additional information about epidermolysis bullosa simplex?

You may find the following resources about epidermolysis bullosa simplex helpful. These materials are written for the general public.

MedlinePlus - Health information
Encyclopedia: Epidermolysis bullosa (http://www.nlm.nih.gov/ medlineplus/ ency/ article/ 001457.htm)
Health Topic: Skin Conditions (http://www.nlm.nih.gov/ medlineplus/ skinconditions.html)
Genetic and Rare Diseases Information Center - Information about genetic conditions and rare diseases (http://rarediseases.info.nih.gov/ GARD/ Disease.aspx? PageID= 4& DiseaseID= 2147)

Additional NIH Resources - National Institutes of Health
National Institute of Arthritis and Musculoskeletal and Skin Diseases (http://www.niams.nih.gov/ Health_ Info/ Epidermolysis_ Bullosa/ default.asp)

Educational resources - Information pages

Madisons Foundation (http://www.madisonsfoundation.org/ index.php/ component/ option, com_ mpower/ diseaseID, 408/)
NetWellness (http://www.netwellness.org/ question.cfm/ 11899.htm)
New York Online Access to Health (http://www.noah-health.org/ en/ skin/ conditions/ epidermolysis.html)
Orphanet (http://www.orpha.net/ consor/ cgi- bin/ OC_ Exp.php? Lng= EN& Expert= 304)

Patient support - For patients and families

DebRA UK (http://www.debra.org.uk/)
Dystrophic Epidermolysis Bullosa Research Association of America (http://www.debra.org/)
Epidermolysis Bullosa Center, Cincinnati Children's Hospital Medical Center (http://www.cincinnatichildrens.org/ svc/ alpha/ e/ epidermolysis- bullosa/)
Epidermolysis Bullosa Medical Research Foundation (http://www.ebkids.org/)
Family Village (http://www.familyvillage.wisc.edu/ lib_ deb.htm)
National Organization for Rare Disorders (http://www.rarediseases.org/ search/ rdbdetail_ abstract.html? disname= Epidermolysis+ Bullosa)
Resource list from the University of Kansas Medical Center (http://www.kumc.edu/ gec/ support/ epidermo.html)
You may also be interested in these resources, which are designed for healthcare professionals and researchers.
Gene Reviews - Clinical summary (http://www.ncbi.nlm.nih.gov/ bookshelf/ br.fcgi? book= gene& part= ebs)
Gene Tests - DNA tests ordered by healthcare professionals (http://www.ncbi.nlm.nih.gov/ sites/ GeneTests/ lab/ clinical_ disease_ id/ 53753)
ClinicalTrials.gov - Linking patients to medical research (http://clinicaltrials.gov/ search/ condition= %22 epidermolysis+ bullosa+ simplex%22 + OR+ %22 Epidermolysis+ Bullosa%22)
PubMed - Recent literature (http://www.ncbi.nlm.nih.gov/ pubmed? term= ( Epidermolysis+ Bullosa+ Simplex[ MAJR] ) + AND+ ( epidermolysis+ bullosa+ simplex[ TIAB] ) + AND+ english[ la] + AND+ human[ mh] + AND+ " last+ 1080+ days" [ dp])

Online Books - Medical and science texts

Scriver's Online Metabolic and Molecular Bases of Inherited Disease (OMMBID): Disorders of Intermediate Filaments and Their Associated Proteins (http://books.mcgraw-hill.com/ getommbid.php? isbn= 0071459960& template= ommbid& c= 221)
Scriver's Online Metabolic and Molecular Bases of Inherited Disease (OMMBID): Epidermolysis Bullosa: The Disease of the Cutaneous Basement Membrane Zone (http://books.mcgraw-hill.com/ getommbid.php? isbn= 0071459960& template= ommbid& c= 222)

OMIM - Genetic disorder catalog

EPIDERMOLYSIS BULLOSA SIMPLEX, LOCALIZED (http://www.ncbi.nlm.nih.gov/ omim/ 131800)
EPIDERMOLYSIS BULLOSA SIMPLEX, AUTOSOMAL RECESSIVE (http://www.ncbi.nlm.nih.gov/ omim/ 601001)
EPIDERMOLYSIS BULLOSA SIMPLEX, OGNA TYPE (http://www.ncbi.nlm.nih.gov/ omim/ 131950)
EPIDERMOLYSIS BULLOSA SIMPLEX WITH MOTTLED PIGMENTATION (http://www.ncbi.nlm.nih.gov/ omim/ 131960)

What other names do people use for epidermolysis bullosa simplex?

Epidermolysis Bullosa Simplex, Generalized
Epidermolysis Bullosa Simplex, Localized

See How are genetic conditions and genes named? (http://ghr.nlm.nih.gov/ handbook/ mutationsanddisorders/ naming) in the Handbook.

What if I still have specific questions about epidermolysis bullosa simplex?

Ask the Genetic and Rare Diseases Information Center (http://rarediseases.info.nih.gov/ GARD/).

What glossary definitions help with understanding epidermolysis bullosa simplex?
autosomal ; autosomal dominant ; autosomal recessive ; blister ; cell ; dehydration ; epidermis ; gene ; infection ; inheritance ; injury ; keratin ; mutation ; new mutation ; pigmentation ; prevalence ; protein ; recessive ; sign ; symptom ; trauma

You may find definitions for these and many other terms in the Genetics Home Reference Glossary (http://ghr.nlm.nih.gov/glossary).

References

Gene Review: Epidermolysis Bullosa Simplex (http://www.ncbi.nlm.nih.gov/ bookshelf/ br.fcgi? book= gene& part= ebs)

Irvine AD. Inherited defects in keratins. Clin Dermatol. 2005 Jan-Feb;23(1):6-14. Review. (http://www.ncbi.nlm.nih.gov/ pubmed/ 15708284? dopt= Abstract)

Pfendner E, Rouan F, Uitto J. Progress in epidermolysis bullosa: the phenotypic spectrum of plectin mutations. Exp Dermatol. 2005 Apr;14(4):241-9. Review. (http://www.ncbi.nlm.nih.gov/ pubmed/ 15810881? dopt= Abstract)

Pfendner EG, Sadowski SG, Uitto J. Epidermolysis bullosa simplex: recurrent and de novo mutations in the KRT5 and KRT14 genes, phenotype/genotype correlations, and implications for genetic counseling and prenatal diagnosis. J Invest Dermatol. 2005 Aug;125(2):239-43. (http://www.ncbi.nlm.nih.gov/ pubmed/ 16098032? dopt= Abstract)

Porter RM, Lane EB. Phenotypes, genotypes and their contribution to understanding keratin function. Trends Genet. 2003 May;19(5):278-85. Review. (http://www.ncbi.nlm.nih.gov/ pubmed/ 12711220? dopt= Abstract)

Rugg EL, Horn HM, Smith FJ, Wilson NJ, Hill AJ, Magee GJ, Shemanko CS, Baty DU, Tidman MJ, Lane EB. Epidermolysis bullosa simplex in Scotland caused by a spectrum of keratin mutations. J Invest Dermatol. 2007 Mar;127(3):574-80. Epub 2006 Oct 12. (http://www.ncbi.nlm.nih.gov/ pubmed/ 17039244? dopt= Abstract)

Rugg EL, Leigh IM. The keratins and their disorders. Am J Med Genet C Semin Med Genet. 2004 Nov 15;131C(1):4-11. Review. (http://www.ncbi.nlm.nih.gov/ pubmed/ 15452838? dopt= Abstract)

The resources on this site should not be used as a substitute for professional medical care or advice. Users seeking information about a personal genetic disease, syndrome, or condition should consult with a qualified healthcare professional. See How can I find a genetics professional in my area? (http://ghr.nlm.nih.gov/ handbook/ consult/ findingprofessional) in the Handbook.

Reviewed: April 2007
Published: December 5, 2010