RÉSUMÉ
Herein, the case of a 43-year-old woman, with a relapsing-remitting variant of multiple sclerosis (MS), which began when she was 34 years of age, and gave rise to severe neurological complications, including progressive paralysis in both legs and visual deterioration, is reported. Despite heavy immunomodulatory treatment, her condition relapsed and became aggravated. At this point, the decision was made to perform autologous hematopoietic stem cell transplantation (HSCT). The enrichment of CD34+ cells was followed by depletion of the peripheral T cells. The post-transplantation course was uneventful, and autoimmune thrombocytopenia developed within 7 months of the HSCT. The patient was treated with cyclosporine (CsA) and oral prednisolone, but subsequently developed systemic sclerosis (SSc). The administration of CsA following the syngeneic/autologous HSCT caused a T lymphocyte-dependent autoimmune disease, which resembled graft-versus-host disease (GVHD). It is quite probable the auto-reactive lymphocytes, which were paradoxically elicited by the CsA during the reconstitution of the immune system, partly contributed to the occurrence of the other autoimmune disease, SSc. To our knowledge, this is the first description of a MS patient, having undergone CD34+-selected autologous HSCT followed by the administration of CsA, who subsequently developed SSc.