Abstract
BACKGROUND/AIM: In patients with non-malignant diseases, mixed chimerism is not a rare phenomenon. The clinical impacts of chimerism following allogeneic haematopoietic stem cell transplantation (allo-HSCT) in children with congenital anaemia (CA) and severe aplastic anaemia (SAA) were analysed. PATIENTS AND METHODS: We studied twenty-seven consecutive children with congenital and acquired anaemia who had undergone allogeneic haematopoietic stem cell transplantations. In the observed group of patients, the median of the follow-up was 6.12 years (2.00-14.8 years). RESULTS: Overall survival (OS) did not depend on the type of disease p=0.1. OS did not significantly differ in patients who received more than 5x10(6)/kg stem cells (91%) and those who received less than 5x10(6)/kg (85%) (p=0.61). Two patterns of stable mixed chimerism (SMC) were observed: SMC (95-97% cells of the donor), and SMC with a fluctuation between 50-90% of the cells of the donor. None of the surviving patients received immunosuppression treatments of chronic Graft-versus-Host Disease (cGvHD). CONCLUSION: Our results showed that mixed chimerism did not influence the survival of children with congenital and aplastic anaemia following allo-HSCT.