The skin biopsy in the diagnosis of acute graft-versus-host disease in man.

Criteria for diagnosis of acute graft-versus-host disease (GVHD) using skin biopsies were derived from a) general experience with more than 300 human marrow grafts and b) the results of "blind" studies of skin biopsy specimens of patients grafted with either allogeneic or syngeneic marrow. Large doses of cytotoxic drugs and irradiation given before grafting can produce transient skin changes interfering significantly with the diagnosis of GVHD. Artifacts can also cause difficulty. Epidermal cytologic atypia, dyskeratosis, and satellitosis were present both in allografted patients with acute clinical GVHD of multiple systems and in patients given autologous or syngeneic marrow. Due to the marked overlap in histopathologic findings between these two types of skin injury, frequent serial skin biopsies must be combined with all other available clinical and biopsy data to provide reliable diagnosis of acute GVHD in man.