Chronic graft-versus-host disease

**Definition:** Chronic graft-versus-host disease (GVHD) presents more than 100 days after engraftment of immunocompetent donor lymphoid cells. It has specific clinical features by which it can be distinguished from acute GVHD. It may arise de novo but frequently follows acute GVHD. Less commonly, it occurs concurrently with acute GVHD. The earlier stages of chronic GVHD are characterised by a widespread lichenoid rash, poikiloderma and involvement of nails and oral mucous membranes. If the disease remains active, progressive sclerosis of the skin and deeper tissues may result in joint contractures, fibrosis of internal organs and severe malabsorption.