Autoimmune rheumatologic diseases
Introduction: Systemic sclerosis (SSc) is a multisystem autoimmune disease with heterogeneous clinical manifestations. Deeper knowledge of pathogenesis of SSc has initiated a new era in treatment with autologous hematopoietic stem cell transplantation (HSCT). It prevents and even reverses damage from autoimmune diseases. The first successful HSCT for SSc was reported in 1997. Thereafter several trials were conducted which revealed significant improvement in outcome.
Discussion: HSCT is a multistep process including mobilization of HSCs from bone marrow or blood, conditioning with immunoablative therapy and reinfusion of HSCs. Inclusion criteria are as follows: diffuse SSc with organ involvement, early-stage of disease < 5 years, mRSS >15, age < 65, lung disease with FVC or DLCO between 45-80% of predicted. Since 2001, three prospective, controlled trials have been conducted to evaluate efficacy, safety and long-term side effects of Autologous HSCT compared to cyclophosphamide. ASSIST: phase II trial reported significant improvement in HSCT group compared to control group. ASTIS: phase III trial revealed a better long-term event-free survival in HSCT group compared to control group although early treatment-related mortality was 10.1%. SCOT: phase III trial which applied total body irradiation and equine anti-thymocyte globulin in conditioning phase which make it different from two other studies. This study follows similar endpoints and is still ongoing.
Conclusion: SSc is an autoimmune disease with high level of mortality and morbidity. HSCT might bring new hopes for patients with diffuse SSc, but more investigations are necessary to answer which patient will get more benefit of HSCT and how to decrease treatment-related mortality.
Nassau University Medical Center