Immunoablation and autologous hematopoietic stem cell transplantation in the treatment of new-onset type 1 diabetes mellitus: long-term observations.

The activity of the autoimmune mechanism underlying type 1 diabetes mellitus (T1DM) can be suppressed when immunoablation and autologous hematopoietic stem cell transplantation (AHSCT) are applied early in the course of the disease. We report here a single centre experience with this treatment modality. Twenty-four patients underwent a AHSCT preceded by immunoablative conditioning with high-dose cyclophosphamide and anti-thymocyte globulin. During the 52-month median time of follow-up 20 out of 23 patients (87%) remained for at least 9.5 months without the use of exogenous insulin. The median time of T1DM remission for these patients was 31 months (range of 9.5-80 months). Among the patients available for follow-up (n=20), four remain insulin free (for 80, 61, 42 and 34 months). The average glycated hemoglobin (HbA1c) concentrations were 10.9% at diagnosis, 5.9% at 1 year, 6.4% at 2 years, 6.8% at 3 years and 7.1% at 4 years after AHSCT. No severe complications of diabetes were seen, however one of the patients died of pseudomonas sepsis in the course of neutropenia after AHSCT. AHSCT leads to a remission of T1DM with good glycemic control in the vast majority of patients, with the period of remission lasting over 5 years in some patients.