Objective: To investigate the differences in immune reconstitution, hematopoietic reconstitution, efficacy, and complication between the two conditioning regimens with or without total body irradiation (TBI) in patients with refractory and severe autoimmune diseases (AID) who receiving autologous peripheral blood stem cell transplantation (APBSCT).
Methods: Thirty-two AID patients, 5 males and 27 females, aged 29 (15 - 49), underwent APBSCT. The CD34(+) cells were mobilized with cytoxan (CTX) + granulocyte-colony stimulating factor (G-CSF) and selected by clinical magnetic activated cell sorting (CliniMACS). The conditioning regimen included CTX + antithymocyte globulin (ATG) in 11 patients and CTX + TBI in 21 patients. All the patients were followed up for more than 12 months.
Results: The median time of granulocyte recovery were 11 and 9 days in the CTX + TBI and CTX + ATG groups respectively (P = 0.003), the median time of platelet recovery were 13 and 8 days respectively (P = 0.001). In both groups, the lymphocyte subsets were recovered with the inverted CD4/CD8 ratio 12 months after transplantation. Relapse was seen in 3 cases of the CTX + TBI group (14.3%), and 2 cases of the CTX + ATG group (18.2%), and the rest of patients remained free of AID. During transplantation incidence of bacteria infection occurred in 5 of the 21 cases in the CTX + TBI group (23.8%) and in 2 of the 11 cases of the CTX + ATG group (18.2%) respectively; viral infection occurred in 1 of the 21 cases of the CTX + TBI group (4.8%) and in 2 of the 11 cases of the CTX + ATG group (18.2%) respectively. The number of radiated parotitis was 4 among the 21 patients of the CTX + TBI group (19%) and was 3 among the 12 patients of the CTX + ATG group (25%). Serum sickness reaction occurred in 3 of the 12 patients of the CTX + ATG group (25%). Bacterial and viral infections were cured soon after antibacterial or antiviral therapy, no fatal bleeding occurred due to thrombocytopenia in both groups.
Conclusion: The conditioning regimen of TBI + CTX delays the hematopoietic reconstitution compared with the ATG + CTX regimen in treating AID. The regimen of CTX + TBI can be better tolerated, but there are no significant differences in efficacy and immune reconstitution among these two regimens.