Haploidentical bone marrow transplantation in a pediatric patient with Wiskott-Aldrich syndrome. A case report.

Wiskott-Aldrich syndrome (WAS) is an X-linked genetic disorder caused by mutations in the gene that encodes the Wiskott-Aldrich syndrome protein (WASp). Here, we report the clinical case of an 18-month-old boy diagnosed with Wiskott-Aldrich syndrome, who did not have an HLA-matched related or unrelated donor and was treated successfully with a hematopoietic stem cell transplant (HSCT) from a haploidentical family donor. Graft-versus-host disease (GvHD) prophylaxis included post-transplant cyclophosphamide (PT-Cy). At day +30, the peripheral blood-nucleated cell chimerism was 100% and the WAS protein had a normal expression. Currently, at month 32 post-transplant, the patient has hematological and immune reconstitution and complete donor chimerism without evidence of GvHD. HSCT with PT-Cy was a feasible and safe option for this patient with WAS, in which an HLA matched donor was not available.