GRAFT-VERSUS-HOST SKIN-DISEASE

Graft versus host disease is frequently encountered in patients with a n allogenic bone marrow transplantation. The disease apparently result s from the activity of the donor T lymphocytes which react against the recipient's cells. There are two categories of graft versus host dise ase: the acute form which occurs within 3 months of the graft and the chronic form which occurs thereafter. Skin is the predominant site of manifestations, although the liver, the gut and the eye may be involve d. In acute graft versus host disease, there is a characteristic macul o-papular rash raising a difficult differential diagnosis which pathol ogy examination of biopsy cannot always resolve. The chronic disease i s easier to recognize on the basis of local or generalized lichenoid o r sclerodermal skin lesions. Several risk factors have been identified including the degree of donor-recipient HLA mismatch, recipient age a nd the number of T cells grafted. Graft versus host disease leads to i mmune deficiency with lymphoid depletion and increased risk of infecti on. Treatment depends on the site of organ involvement and extension. Corticosteroids and immunosuppressors are used.