Anti-programmed cell death-1-induced plaque and guttate psoriasis

Psoriasiform plaques were scattered on the dorsum of hands [Figure 1]a, whereas small, scaly erythemas were observed on the soles [Figure 1]b. He denied either sore throat or upper respiratory tract infection. Laboratory examinations showed normal eosinophil ratio (0.8%) in the peripheral blood, mild increased level of C-reactive protein (1.7 mg/dl), and normal liver and renal functions. A skin biopsy from the dorsum of the hand revealed mild parakeratotic hyperkeratosis, regular acanthosis, mild telangiectasia in the papillary dermis, and mild infiltration of lymphocytes admixed with a small number of neutrophils [Figure 1]c. Another specimen from the sole also showed epidermal proliferation with parakeratosis in the thickened cornified layers and moderate perivascular infiltration of mononuclear cells [Figure 1]d. The infiltrating cells were mainly composed of intraepidermal and dermal CD8-positive T-cells and CD3- and CD4-positive T-cells in the dermis [Figure 1]e and [Figure 1]f. The patient was being treated with topical corticosteroids without discontinuation of nivolumab.