Ten-Year Remission of Psoriasis after Allogeneic but Not Autologous Bone Marrow Transplantation

The psoriatic skin lesion is characterized by infl ammation, with T cells and neutrophils infi ltrating the dermis and epidermis. The excessive scaling is related to epidermal hyperproliferation and aberrant keratinocyte differentiation. As T cells are important in the pathogenesis of psoriasis [1] , one might expect that bone marrow transplantation (BMT) might alter the course of the disease. Evidence that such a phenomenon exists comes from experimental mouse animal models [2] . Furthermore, there are some clinical case reports which demonstrate the long-term resolution of psoriasis after allogeneic BMT [3–5] and the relapse of psoriasis after autologous BMT [6] . In this report, we describe 2 psoriatic patients. One received allogeneic BMT and his psoriasis resolved completely. He has been in remission for more than 10 years. The second patient received autologous BMT and after 21 months in remission his psoriasis returned. This illustrates that an immune-mediated disease such as psoriasis may resolve completely or for a long time after allogeneic BMT, but a single autograft with unpurged stem cells is unlikely to cure such a disorder.