Leukomelanoderma following acute cutaneous graft-versus-host disease

Acute graft versus host disease (GVHD) is characterized by a selective epithelial inflammation that can affect the skin, digestive tract, and liver. Development of pigmentary abnormalities can be observed in sites where acute cutaneous GVHD has occurred, and usually consists of hyperpigmented spots. We observed atypical pigmetary changes consisting of a combination of hyper- and hypopigmentation, so called leukomelanoderma, in a young allogeneic bone marrow recipient who suffered repetitive acute GVHD. The histopathological examinations showed features of a post-inflammatory process. Because keratinocytes produce inflammatory cytokines including tumor necrosis factor (TNF)-alpha and interleukin (IL)-1alpha, which may be implicated in the inflammatory phenomena seen in acute GVHD, we studied whether these inflammatory cytokines might be implicated in these pigmentary changes. The cytokines tested were IL-1alpha, IL-2, TNF-alpha and IL-10. The expression of TNF-alpha increased in the hyperpigmented skin relative to normal and hypopigmented skin. While TNF-alpha was variably distributed in proportion to different degrees of pigmentation, other molecules were detected at minimal levels in all samples. This observation may indicate that the production of TNF-alpha by epidermal microenvironment may be involved in postinflammatory pigmentary changes.