Antiepiligrin cicatricial pemphigoid: An underdiagnosed entity within the spectrum of scarring autoimmune subepidermal bullous diseases?

Background: Antiepiligrin cicatricial pemphigoid (AECP) is a chronic autoimmune subepidermal blistering disease characterized by autoantibodies to laminin 5 and clinical features of cicatricial pemphigoid. Only a few patients with AECP have been described to date. The aim of the present study was to analyze the relative frequency of AECP among patients with the clinical phenotype of cicatricial pemphigoid. Observations: Serum from 16 consecutive patients with the clinical phenotype of cicatricial pemphigoid were included in this study. Nine patients had circulating IgG autoantibodies by indirect immunofluorescence on sodium chloride-split skin; patients' IgG bound to the epidermal side (n = 2), dermal side (n = 5), or both sides (n = 2) of this test substrate. Interestingly, all 5 cases with dermal binding immunoprecipitated laminin 5 from extracts and media of cultured keratinocytes, and 4 of these serum samples reacted with the α3 subunit of laminin 5 by immunoblotting. None of the patients with dermal binding of IgG demonstrated autoantibodies to type VII collagen. Conclusion: Our data suggest that, among patients with the clinical phenotype of cicatricial pemphigoid, AECP may be more frequent than previously assumed.