[Treatment of lichen planus pemphigoides with acitretin and pulsed corticosteroids].

A patient with lichen planus pemphigoides first developed multiple pruritic papules and subsequently, tense blisters on trunk and extremities. Histopathologic examination of a skin biopsy demonstrated both the typical changes of lichen planus and subepidermal blisters as in bullous pemphigoid. Direct immunofluorescence microscopy revealed both cytoid bodies and linear C3 deposits at the dermal-epidermal junction. By indirect immunofluorescence microscopy on 1 M NaCl-split-skin, circulating autoantibodies labeled the epidermal side of the split. Immunoblot analysis showed binding of the antibodies to the cell-derived soluble 120 kD domain of the 180 kD bullous pemphigoid antigen and to a recombinant form of the immunodominant NC16A region of this protein. When treated with pulsed intravenous corticosteroids, the patient continued to develop new papules and blisters, but when oral acitretin was added, the skin lesions cleared. The immunoblot reactivity of the patient's autoantibodies well reflected disease activity, while the indirect immunofluorescence microscopy titers did not.