Photo-induced graft-versus-host disease

Juliette M Hardy1, Marie-Claude Marguery1, Anne Huynh2

  • 1Department of Dermatology, Toulouse University Hospital, Paul Sabatier University, Toulouse, France.

Overlap chronic graft-versus-host disease (GVHD) associates both features of acute and chronic GVHD. Trigger factors for chronic GVHD are unclear. We describe two patients who received allogenic haematopoietic stem-cell transplantation, and who later developed overlap chronic GVHD after sun exposure. Available data from in vivo investigations suggest ultraviolet B radiation (UVB) has a beneficial effect on acute and chronic GVHD. The role of sun irradiation as a trigger for isomorphic cutaneous GVHD has been rarely reported in the literature. Herein, we demonstrate for the first time, using repetitive broadband phototesting, that UVB triggers chronic GVHD.