Mucosal "peeling" biopsy technique for the immunopathologic evaluation of desquamative gingivitis-associated mucous membrane pemphigoid.

D ESQUAMATIVE GINGIVITIS CAN RESULT from various pathogenetic factors, including mucous membrane pemphigoid (MMP). Adequate gingival sampling for immunopathologic evaluation is mandatory for the diagnosis of MMP. The gingival mucosal “peeling” biopsy technique (Figure 1) yields sufficient epithelium samples for histologic analysis and direct immunofluorescence (DIF). Hemidesmosomal proteins (BPAG1-2 and 6 4-integrin) are the most common MMP autoantigens, resulting in a “capping hemidesmosomal” linear IgG DIF pattern on the gingival epithelial undersurface (Figure 2). To circumvent false-negative DIF results, related to less common, deeper basement membrane zone autoantigens (laminin5/6 and collagenVII), serologic evaluation for anti–basement membrane zone autoantibodies (eg, indirect immunofluorescence and enzyme-linked immunosorbent assay) should be performed. If the findings of DIF and serologic studies are nondiagnostic and a high index of clinical suspicion for MMP remains, an appropriate mucosal punch or incisional biopsy should be performed. Gingival lesions in patients with MMP may deter clinicians from performing sampling owing to technical difficulty. Mucosal peeling can provide adequate immunopathologic samples for the diagnosis of desquamative gingivitis– associated MMP.