Acute follicular graft-vs-host reaction. A distinct clinicopathologic presentation.

Human graft-vs-host disease (GVHD) is a life-threatening complication that may occur following allogeneic bone marrow transplantation. In acute GVHD, skin involvement is frequent, and the skin is often the initial organ involved. The rash typically is a blanchable, erythematous macular eruption. We present the first report of follicular cutaneous GVHD. Three patients developed follicular papules simulating bacterial or fungal folliculitis as a major clinical expression of cutaneous involvement in acute GVHD following allogeneic bone marrow transplantation. In each case, histopathologic examination demonstrated features of acute graft-vs-host reaction involving hair follicles. This suggests that follicular epithelium may be an early target in acute GVHD.