PMC10240285_01
(A-C) The diffuse erythema, tense bullae and erosions involved both upper limbs; (D,E) skin biopsy revealed a subepidermal blister and the superficial dermal inflammation consisting of lymphocytes and eosnophils; (F) direct immunofluorescence demonstrated linear deposits of IgG along basement membrane zone; (G-I) improvement of skin lesions after 1 week of treatment; (J) the timeline of the patient's clinical symptoms.
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F1
Two weeks after the first injection, he developed blisters on his upper limbs (Figures 1A, B). However, the pruritic blisters on his upper limbs reappeared 1 week after the second ustekinumab injection (Figure 1C). Histologic examination showed a subepidermal blister and superficial dermal inflammation comprising lymphocytes and eosinophils (Figures 1D, E). Direct immunofluorescence showed linear IgG staining along the basement membrane zone (Figure 1F). The skin lesions improved significantly after 2 weeks (Figures 1G-I). The timeline is summarized in Figure 1J.