Epidermolysis bullosa simplex with pyloric atresia (EBS-PA) is a basal subtype of epidermolysis bullosa simplex (EBS, see this term) characterized by generalized severe blistering with widespread congenital absence of skin and pyloric atresia.
Prevalence is unknown, but at least 12 families have been reported to date.
Onset is at birth and babies are usually born prematurely with a low weight and poor general condition. Pyloric atresia can be suspected antenatally based on polyhydramnios and is confirmed at birth by abdominal X-ray examination. Additional extracutaneous findings include failure to thrive, anemia, sepsis, intraoral blistering, malformed pinnae and nasal alae, and joint contractures.
Most EBS-PA cases are due to mutations in the PLEC gene (8q24) encoding the plectin 1 protein. Recently, it has also been shown that PLEC mutations can lead to both muscular dystrophy and pyloric atresia phenotypes in an individual EBS patient. In addition, in rare cases mutations in the ITGB4 gene encoding the beta4 subunit of alpha6 beta4 integrin can result in tissue separation within basal keratinocytes, thus corresponding to EBS-PA cases (most cases of ITGB4 and ITGA6 gene mutations are responsible for junctional epidermolysis bullosa with pyloric atresia; see this term).
Transmission is autosomal recessive.
In most cases, EBS-PA has a fatal outcome in early infancy despite surgical correction of pyloric atresia.
Last update: May 2012