Submitted Successfully!
To reward your contribution, here is a gift for you: A free trial for our video production service.
Thank you for your contribution! You can also upload a video entry or images related to this topic.
Version Summary Created by Modification Content Size Created at Operation
1 + 686 word(s) 686 2020-12-15 07:22:53

Video Upload Options

Do you have a full video?


Are you sure to Delete?
If you have any further questions, please contact Encyclopedia Editorial Office.
Yin, N. Epidermolysis Bullosa with Pyloric Atresia. Encyclopedia. Available online: (accessed on 23 June 2024).
Yin N. Epidermolysis Bullosa with Pyloric Atresia. Encyclopedia. Available at: Accessed June 23, 2024.
Yin, Nicole. "Epidermolysis Bullosa with Pyloric Atresia" Encyclopedia, (accessed June 23, 2024).
Yin, N. (2020, December 25). Epidermolysis Bullosa with Pyloric Atresia. In Encyclopedia.
Yin, Nicole. "Epidermolysis Bullosa with Pyloric Atresia." Encyclopedia. Web. 25 December, 2020.
Epidermolysis Bullosa with Pyloric Atresia

Epidermolysis bullosa with pyloric atresia (EB-PA) is a condition that affects the skin and digestive tract. This condition is one of several forms of epidermolysis bullosa, a group of genetic conditions that cause the skin to be fragile and to blister easily. Affected infants are often born with widespread blistering and areas of missing skin. Blisters continue to appear in response to minor injury or friction, such as rubbing or scratching. Most often, blisters occur over the whole body and affect mucous membranes such as the moist lining of the mouth and digestive tract.

genetic conditions

1. Introduction

People with EB-PA are also born with pyloric atresia, which is a blockage (obstruction) of the lower part of the stomach (the pylorus). This obstruction prevents food from emptying out of the stomach into the intestine. Signs of pyloric atresia include vomiting, a swollen (distended) abdomen, and an absence of stool. Pyloric atresia is life-threatening and must be repaired with surgery soon after birth.

Other complications of EB-PA can include fusion of the skin between the fingers and toes, abnormalities of the fingernails and toenails, joint deformities (contractures) that restrict movement, and hair loss (alopecia). Some affected individuals are also born with malformations of the urinary tract, including the kidneys and bladder.

Because the signs and symptoms of EB-PA are so severe, many infants with this condition do not survive beyond the first year of life. In those who survive, the condition may improve with time; some affected individuals have little or no blistering later in life. However, many affected individuals who live past infancy experience severe health problems, including blistering and the formation of red, bumpy patches called granulation tissue. Granulation tissue most often forms on the skin around the mouth, nose, fingers, and toes. It can also build up in the airway, leading to difficulty breathing.

2. Frequency

EB-PA appears to be a rare condition, although its prevalence is unknown. At least 100 affected individuals have been reported worldwide.

3. Causes

EB-PA can be caused by mutations in the ITGA6, ITGB4, and PLEC genes. These genes provide instructions for making proteins with critical roles in the skin and digestive tract.

ITGB4 gene mutations are the most common cause of EB-PA; these mutations are responsible for about 80 percent of all cases. ITGA6 gene mutations cause about 5 percent of cases. The proteins produced from the ITGA6 and ITGB4 genes join to form a protein known as α6β4 integrin. This protein plays an important role in strengthening and stabilizing the skin by helping to attach the top layer of skin (the epidermis) to underlying layers. Mutations in either the ITGA6 gene or the ITGB4 gene lead to the production of a defective or nonfunctional version of α6β4 integrin, or prevent cells from making any of this protein. A shortage of functional α6β4 integrin causes cells in the epidermis to be fragile and easily damaged. Friction or other minor trauma can cause the skin layers to separate, leading to the formation of blisters.

About 15 percent of all cases of EB-PA result from mutations in the PLEC gene. This gene provides instructions for making a protein called plectin. Like α6β4 integrin, plectin helps attach the epidermis to underlying layers of skin. Some PLEC gene mutations prevent the cell from making any functional plectin, while other mutations result in an abnormal form of the protein. When plectin is altered or missing, the skin is less resistant to friction and minor trauma and blisters easily.

Researchers are working to determine how mutations in the ITGA6, ITGB4, and PLEC genes lead to pyloric atresia in people with EB-PA. Studies suggest that these genes are important for the normal development of the digestive tract.

4. Inheritance

This condition is inherited in an autosomal recessive pattern, which means both copies of the gene in each cell have mutations. The parents of an individual with an autosomal recessive condition each carry one copy of the mutated gene, but they typically do not show signs and symptoms of the condition.

5. Other Names for This Condition

  • Carmi syndrome
  • EB-PA
  • junctional epidermolysis bullosa with pyloric atresia
  • PA-JEB


  1. Pfendner E, Uitto J. Plectin gene mutations can cause epidermolysis bullosawith pyloric atresia. J Invest Dermatol. 2005 Jan;124(1):111-5.
  2. Pfendner EG, Bruckner A, Conget P, Mellerio J, Palisson F, Lucky AW. Basicscience of epidermolysis bullosa and diagnostic and molecular characterization:Proceedings of the IInd International Symposium on Epidermolysis Bullosa,Santiago, Chile, 2005. Int J Dermatol. 2007 Aug;46(8):781-94.
  3. Pfendner EG, Lucky AW. Epidermolysis Bullosa with Pyloric Atresia. 2008 Feb 22[updated 2017 Sep 7]. In: Adam MP, Ardinger HH, Pagon RA, Wallace SE, Bean LJH,Stephens K, Amemiya A, editors. GeneReviews® [Internet]. Seattle (WA): Universityof Washington, Seattle; 1993-2020. Available from
  4. Pulkkinen L, Kim DU, Uitto J. Epidermolysis bullosa with pyloric atresia:novel mutations in the beta4 integrin gene (ITGB4). Am J Pathol. 1998Jan;152(1):157-66.
  5. Pulkkinen L, Kimonis VE, Xu Y, Spanou EN, McLean WH, Uitto J. Homozygousalpha6 integrin mutation in junctional epidermolysis bullosa with congenitalduodenal atresia. Hum Mol Genet. 1997 May;6(5):669-74.
  6. Pulkkinen L, Uitto J. Mutation analysis and molecular genetics ofepidermolysis bullosa. Matrix Biol. 1999 Feb;18(1):29-42. Review.
  7. Varki R, Sadowski S, Pfendner E, Uitto J. Epidermolysis bullosa. I. Molecular genetics of the junctional and hemidesmosomal variants. J Med Genet. 2006Aug;43(8):641-52.
Contributor MDPI registered users' name will be linked to their SciProfiles pages. To register with us, please refer to :
View Times: 324
Entry Collection: MedlinePlus
Revision: 1 time (View History)
Update Date: 25 Dec 2020
Video Production Service