Pyloric atresia with junctional epidermolysis bullosa (PA-JEB) syndrome: Absence of detectable β4 integrin and reduced expression of epidermal linear IgA dermatosis antigen

A newborn girl with pyloric atresia with junctional epidermolysis bullosa (PA-JEB) developed vomiting and blisters after birth. Radiography revealed pyloric atresia, and a resection of atretic segment and gastroduodenostomy were carried out at 4 days after birth. Physical examination revealed multiple bullae on the trunk and extremities (Fig. 1). Light microscopy of a skin biopsy specimen showed subepidermal bullae with few inflammatory cells. Electron microscopy showed separation in the lamina lucida and rudimentary hemidesmosomes (Fig. 2). A direct immunofluorescence (IF) mapping study was negative for immunoglobulin G (IgG), IgA, IgM, C3, and fibrin. To determine the cleavage level, an IF mapping study was performed on 6 μm cryostat sections of a frozen skin biopsy specimen, using bullous pemphigoid (BP) antibody, monoclonal antibody against type IV collagen (Dako, Copenhagen, Denmark), monoclonal antibody (LH 7.2) against type VII collagen (Serotec, Oxford, UK), and epidermolysis bullosa acquisita (EBA) serum. The staining for BP was identified on the epidermal side. The staining for monoclonal antibody against type IV collagen, type VII collagen, and EBA was identified on the dermal side. This pattern was compatible with the diagnosis of JEB. We also performed an IF mapping study using GB3 monoclonal antibody (Sera Laboratory, Cambridge, UK), which recognizes laminin 5 monoclonal antibody against β4 integrin (Chemicon, Los Angeles, CA), and linear IgA dermatosis (LAD) antibody, which binds to the epidermal side of salt-split skin substrate (Fig 3). The patient's skin has normal laminin 5 expression, but an absence of detectable β4 integrin and reduced epidermal LAD antigen expression. Despite nutritional support with parenteral nutrition and special formula feeding, chronic diarrhea and bloody mucoid stools persisted and malnutrition was not improved.