Long-term persistent mixed chimerism in a patient with Wiskott–Aldrich syndrome after allogeneic hematopoietic stem cell transplantation

The article describes a clinical case of a patient with Wiskott–Aldrich syndrome, in whom long- term persistence of mixed chimerism was determined after hematopoietic stem cell transplantation (HSCT) from a haploidentical donor. Based on the analysis of the patient's clinical picture after HSCT, it was shown that the presence of> 50% of donor cells in the myeloid lineage is necessary for the correction of thrombocytopenia. In addition, the presence of mixed chimerism in B-lymphocytes possibly contributed to the development of autoimmune complications in the patient, as well as to the persistent hypogammaglobulinemia, despite the restoration of the normal numbers of lymphocytes in all main sub-populations. The role of mixed chimerism in the pathogenesis of immune post-transplant complications requires study in large groups of patients with primary immunodeficiencies. The patient's parents agreed to use the information, including the child's photo, in scientific research and publications.