[Histopathology of graft-versus-host disease].

Graft-versus-host disease (GvHD) occurs as a major complication in 35%-50% of all patients undergoing allogeneic stem cell transplantation. A distinction is made between acute and chronic GvHD depending on the time of onset, type of clinical symptoms and histology. Both forms preferably show manifestations in the skin, mucosal membranes, gastrointestinal tract, liver and (less often) lung. As the clinical presentation is rather unspecific, particularly for the diagnosis of acute GvHD, histology is important to exclude infectious diseases or drug reactions. This review covers the diagnostic morphological criteria and differential diagnoses of GvHD in the skin, gastrointestinal tract and the liver.