Successful treatment of scleromyxedema with autologous peripheral blood stem cell transplantation

Introduction Scleromyxedema is a rare chronic fibromucinous disorder that can have devastating clinical manifestations, including sclerosis of the skin with progressive pharyngeal and upper airway involvement, resulting in a high mortality due to respiratory complications. It is usually associated with a monoclonal protein, although overt multiple myeloma is rarely present. Current therapeutic strategies are often inadequate, and we describe a novel therapeutic approach. Autologous hematopoietic stem cell transplantation is effective in other low-grade plasmaproliferative disorders, and it was postulated that it may be effective in this setting. Methods We describe two patients with progressive Scleromyxedema who failed to respond to standard therapeutic measures. The first patient had refractory, debilitating disease involving her entire integument, with severe pyoderma faciale and oropharyngeal involvement. Previous therapeutic interventions included antibiotic therapy with cephalexin combined with isotretinoin, prednisone, oral cyclophosphamide, melphalan, PUVA, and plasma exchange. She continued to have progressive disease despite these interventions. The second patient also had progressive disease which failed to respond to isotretinoin but he had no prior alkylator exposure. Melphalan 200 mg/m2 was used as the conditioning regimen and was administered on an outpatient basis. Results The response to autologous hematopoietic progenitor cell transplantation was dramatic in both patients. Within 1 week after melphalan conditioning, progressive improvement in the skin sclerosis and oropharyngeal function was noted and has continued in both patients. This response has been associated with a profound reduction or disappearance of the abnormal plasma cell clone, as documented by serum electrophoresis with immunofixation and bone marrow evaluation with labeling indices. Neither patient has demonstrated clinical or laboratory evidence of relapse at 19 and 8 months post transplant respectively. Conclusion We believe that autologous hematopoietic progenitor cell transplantation should be considered in patients with Scleromyxedema. It is prudent to consider stem-cell harvest before prolonged exposure to melphalan, because alkylating agents can affect the quantity and quality of stem-cell harvests.