COL17A1 and lichen planus: Although BP180/230 autoantibody testing was not available at our institution, several clinical and histopathologic findings made bullous pemphigoid or lichen planus pemphigoides unlikely: absence of tense bullae, lack of mucosal involvement, no subepidermal clefting, absence of eosinophil-rich infiltrates, and a biopsy consistent with classic lichen planus.