predominantly affects mucosal membranes (most often eyes and mouth)
Clinical:
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oral (85-100%): often present as slowly healing erosions
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ocular (65-85%): conjuctivitis(early); 1/3 go on to blindness
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skin (25%)
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Brunsting-Perry variant = head and neck lesions, sparing mucous membranes
ddx:
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of ocular disease: cicatrizing conjunctivitis that results from chronic use of certain ophthalmologic preparations (e.g. pilocarpine, guanethidine, or ephedrine used in the treatment of glaucoma or idocuridine used as an antiviral)
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other autoimmune bullous diseases – Pemphigus Vulgaris, EBA, linear IgA
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erosive oral LP, erythema multiforme, LE, paraneoplastic pemphigus
DIF:
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linear deposition of IgG and complement along BMZ
Pathogenesis:
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autoantibodies appear to recognize a variety of different antigens present in epithelial basement membranes
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IF dermal side of salt-split lights up, THEN the antigen is:
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epiligrin (= laminin 5) - best characterized
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type VII collagen
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IF roof of salt-split lights up, THEN the antigen is:
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BP-2 (180kd) = major antigen in patients with this salt-split pattern