Hematopoietic Cell Transplantation in a Patient With X-Linked Chronic Granulomatous Disease With McLeod Phenotype.

Abstract

Background: X-linked chronic granulomatous disease (X-CGD) may be associated with McLeod syndrome (MLS) as a contiguous gene deletion syndrome. MLS is characterized by the loss of XK protein along with Kx antigen on red blood cell (RBC) surfaces and late-onset neurocognitive symptoms. RBCs in healthy donors express XK protein and related Kx antigen on the surface; therefore, transfusion from random donors to patients with MLS poses a risk of Kx sensitization, leading to severe hemolysis. As the radical treatment of X-CGD is hematopoietic cell transplantation (HCT), treating patients with coexisting X-CGD and MLS is extremely challenging.

Method: A retrospective chart review was completed for a case of X-CGD associated with MLS who underwent HCT.

Result: A 7-year-old boy with X-CGD and MLS underwent HCT from a matched unrelated donor (human leukocyte antigen, 7/8 matched). Rituximab was added to busulfan-based reduced intensity conditioning to prevent Kx sensitization. Donor RBCs were depleted from the bone marrow before infusion to prevent Kx sensitization. Neutrophil engraftment was achieved on day +19 with full donor chimerism. No hemolytic events occurred, and he is living well 2 years after HCT.

Conclusion: We were able to safely perform transplantation in a patient with X-CGD and MLS by adding rituximab and depleting RBCs from the donor bone marrow. The long-term impact of HCT on MLS is unclear. However, HCT may improve prognosis and quality of life by reducing recurrent infections caused by X-CGD. Moreover, this HCT method is non-invasive, relatively simple, and easily implementable.