IIF for EBA using human split skin shows the same basal localisation of linear BMZ fluorescence and anti collagen VII antibody ELISA is useful to confirm EBA, differentiate it from dermal-binding (laminin) pemphigoid cases and to help guide treatment decisions, since circulating anti COLVII antibody levels correlate with disease activity [75]. This evidence concerns the gene LAMB2 and autoimmune bullous skin disease.