The optimal oral biopsy site for diagnosis of mucous membrane pemphigoid and pemphigus vulgaris

Background Accepted 'standard practice' for the diagnosis of immunobullous disease is a perilesional sample for direct immunofluorescence (DIF). Objectives To compare diagnostic outcomes of a normal buccal punch biopsy (NBPB) with a perilesional biopsy (PLB) for mucous membrane pemphigoid (MMP) and pemphigus vulgaris (PV). Methods A retrospective analysis of 251 DIF-positive patients with MMP and 77 DIF-positive patients with PV was undertaken. Parameters analysed included the intraoral sites of involvement and histopathological, DIF and indirect immunofluorescence (IIF) findings. Results For MMP, PLB was positive in 134 of 143 (93 center dot 7%) samples, compared with 129 of 144 (89 center dot 6%) by NBPB. The diagnostic sensitivities for PLB (81%, 39 of 48) and NBPB (77%, 37 of 48) among 48 patients who underwent both techniques were not significantly different (P = 0 center dot 62). In gingival-only MMP, PLB was positive in 63 of 69 (91%) and NBPB was positive in 63 of 75 (84%). For multisite MMP, PLB was positive in 71 of 74 (96%) and NBPB was positive in 66 of 69 (96%). In gingival-only MMP, biopsies from reflected alveolar mucosa in 17 consecutive patients were positive in 17 of 17 cases (100%). For PV, PLB was positive in 42 of 43 (98%), compared with 42 of 42 (100%) by NBPB. Histopathology was diagnostic in 93 of 134 (69 center dot 4%) cases of MMP and 38 of 41 (93%) cases of PV. IIF was positive in 126 of 197 (64 center dot 0%) MMP and 68 of 74 (92%) PV patient sera. Conclusions In the largest series of combined oral DIF results in patients with MMP and PV, we have shown that NBPB is equivalent to PLB for the diagnosis of PV and multisite MMP, and is more sensitive than both histology and IIF.