Prevalence: 7-52%
Clinical presentations:
(1) mucosal ulceration, typically painless
(2) discoid lesions (central areas of erythema with white spots surrounded by radiating white striae and telangiectasia
(3) erythematous lesions
(4) hyperkeratotic lesions
Histopathologic features:
(1) interface mucositis
(2) hyperkeratosis with keratotic plugging
(3) liquefactive degeneration
(4) perivascular inflammation, usually lymphohistiocytic
(5) intra-epithelial microabscesses
(6) spongiosis
(7) civatte bodies (colloid bodies)
(8) multi-nucleated epithelial cells
Immunohistological findings:
(1) deposits of IgM and IgG along the dermal-epidermal junction
(2) deposits of complement along the dermal-epidermal junction
(3) deposits of fibrinogen along the dermal-epidermal junction
Differential diagnosis:
(1) lichen planus
(2) leukoplakia
(3) infection
(4) drug adverse effects
