Identification of skin‐infiltrating donor lymphocytes in a case of pre‐engraftment syndrome

Abstract

Dear Editor, Umbilical cord transplantation (UCBT) has emerged as an alternative to bone marrow transplantation (BMT) for the treatment of hematologic malignancies due to its permissive HLA mismatching and easier procurement logistics. Engraftment in UCBT is slower but with lower incidence of graft-versus-host disease (GVHD) than conventional BMT. 1,2 Interestingly, UCBT has led to the recognition of pre-engraftment syndrome (PES) as an entity distinct F I G U R E 1 Clinical manifestations and histological findings. (a) Rash on the trunk on day 8 post-UCBT. (b) Clinical finding during PES onset. Neutrophil count (black), lymphocyte count (orange), and body temperature (blue). (c, d) Hematoxylin-eosin staining and rectangle in (c) depict the magnified area in (d). Immunohistochemistry for (e) CD3, (f) CD4, (g) CD8, (h) CD163. Scale bar = 100 μm. (i, j) XY-FISH performed on formalin-fixed paraffin-embedded skin sections from the skin biopsy. Rectangle in (i) depict the magnified area in (j). Arrowhead in (j) depicts a donor-derived cells (XX). Scale bar = 50 μm.