Lichen planus pemphigoides: Case reports and review of the literature

Abstract

Background: Lichen planus pemphigoides (LPP) is a rare autoimmune subepidermal blistering disease that shares clinical and/or immunopathologic features of lichen planus (LP) and bullous pemphigoid (BP). Epitope-spreading phenomenon may play a primordial role in the pathophysiology of this disease. LPP may represent a unique entity or a heterogeneous response to several basal membrane zone (BMZ) injuries, with exposure of different antigens leading to subepidermal blistering. Aim: To characterize two patients from Brazil that fulfilled the criteria for LPP, and to compare them with other reports in the literature. Methods: The diagnosis of LPP was confirmed by clinical, histologic, and immunologic (direct and indirect immunofluorescence, BP180 ELISA, immunoblotting) features. Results: The two patients evaluated in the study showed compatible clinical and laboratory findings of LPP, with lichenoid lesions coexisting with blisters because of the recognition of an autoimmune response against BP180. Conclusion: LPP could be either a single association between LP and BP, a unique condition, or part of a spectral autoimmune disease that recognize BMZ self-antigens. Possible triggersinclude BMZ aggressionsthat lead to an epitope spreading phenomenon.