Inheritance: autosomal recessive
Biochemical Defect: Deficiency of procollagen 1 N-terminal peptidase.
Major criteria:
(1) severe skin fragility
(2) sagging, redundant skin
Minor criteria:
(1) soft, doughy skin texture
(2) easy bruisability
(3) premature rupture of the fetal membranes
(4) large hernias (umbilical, inguinal, incisional, etc.)
(5) family history with affected siblings
Other findings:
(1) Wound healing is not impaired.
(2) Scars are not atrophic.
Laboratory confirmation:
(1) electrophoresis of procollagen chains extracted from dermal fibroblasts
(2) measurement of N-proteinase activity (research)
