Fig. 2. (A~E) Histopathological findings of skin biopsy. (A) Dense inflammatory cell infiltration into the deep dermis (H&E, ×40). (B) Numerous small to medium-sized vascular channels surrounded by densely mixed inflammatory cells, especially abundant epitheloid histiocytes, lymphocytes, and some eosinophils (H&E, ×200). (C) Positive (CD3, ×200). (D) Strong positive (CD68, ×200). (E) Positive (programmed death-1 [PD-1], ×200). (F~L) Histopathological findings of inguinal lymph node biopsy. (F, G) Effacement of normal architecture with an interfollicular mixed polymorphous infiltrate (H&E; F: ×100, G: ×200). (H) Positive (CD3, ×200). (I) Positive (CD4, ×200). (J) Positive (CD5, ×200). (K) Irregular expansion of follicular dendritic cells (CD21, ×100). (L) Positive (PD-1, ×200).
