The use of cyclosporin in a child with generalized pustular psoriasis

SIR, There are various bullous diseases showing autoantibodies to the basement membrane zone (BMZ). Bullous pemphigoid (BP) sera react with the 230 kDa BP antigen (BP230) and/or the 180 kDa BP antigen (BP180). Epidermolysis bullosa acquisita (EBA) sera react with the 290 kDa EBA antigen (type VII collagen). The sera of cicatricial pemphigoid and linear IgA bullous dermatosis show heterogeneous reactivity. In addition, a 200 kDa antigen located in the deeper portion of the lamina lucida has been identified as a novel antigen in a patient with atypical bullous lesions, and patients with longstanding psoriasis associated with blister formation. We present two patients with vesicular pemphigoid-like clinical features, who showed anti-BMZ antibodies against the 200 kDa protein. Patient 1, a 64-year-old Japanese man, developed itchy erythematous skin lesions up to 1 cm in size, associated with crusts and erosions (Fig. 1). Only a few vesicles were seen. An annular arrangement of lesions was occasionally seen. He never developed large tense bullae characteristic of BP. This patient did not respond well to systemic steroids. However, the skin lesions quickly cleared, leaving slight scarring, after administration of dapsone, 100 mg daily. The dosage was tapered to 50 mg daily without recurrence. Patient 2, a 64-year-old Japanese man, developed vesicles and erosions up to 0·5 cm in size, over the entire body. The lesions on the palms and soles resembled palmoplantar pustulosis. Neither large tense bullae nor an annular arrangement of lesions was seen. This patient responded well to a combination of oral prednisolone, 40 mg daily and dapsone, 75 mg daily. This case was reported in a Japanese journal in 1982, without any results of antigen studies. In both cases, histopathological studies showed subepidermal bullae with infiltration predominantly of neutrophils. Direct immunofluorescence (IF) showed IgG and C3 deposition at the BMZ. On indirect IF of 1 mol/L NaCl-split skin, IgG in the sera reacted only with the dermal side of the split. On immunoblotting (IB) of normal human epidermal extracts, the sera did not react with either BP230 or BP180. On IB of recombinant protein of the BP180 NC16a domain, which is known to be recognized by almost all BP sera, the sera showed no reactivity. In contrast, on IB of human dermal extracts, the sera reacted exclusively with a 200 kDa protein, while control EBA sera reacted with the 290 kDa EBA antigen. The 200 kDa band showed exactly the same migration on the gel as in previously reported cases. The present two patients showed only small skin lesions, corresponding to vesicular pemphigoid, and the skin lesions were responsive to dapsone. Linear IgG deposition along the BMZ was detected by direct IF. However, in contrast to BP, the sera of these patients reacted with the dermal side of 1 mol/L NaCl-split skin on indirect IF. On IB of various antigen sources including normal epidermal extracts, dermal extracts and recombinant protein of the BP180 NC16a domain, these sera reacted only with a 200 kDa protein present in the dermal extracts, but not with any other known autoantigens. This 200 kDa antigen has been detected in a patient with atypical bullous lesions and in patients with psoriasis. This study indicates that a subset of patients with the vesicular pemphigoid phenotype may also react with this antigen, although the nature of this 200 kDa antigen has not been characterized.