Hematopoietic stem cell transplantation in pediatric patients with type VI mucopolysaccharidosis.

Background: It is uncertain whether hematopoietic stem cell transplantation (HSCT), versus standard enzyme replacement therapy (ERT), is effective for type VI mucopolysaccharidosis (MPS VI).

Purpose: New related advances in HSCT prompted an examination of the transplant procedures performed in a recent cohort.

Methods: This single-center retrospective study reviewed the medical records of 17 pediatric patients with MPS VI who underwent allogeneic HSCT in 2021-2023. All conditioning regimens were myeloablative. Engraftment days, complications, and survival data were recorded. As follow-up was short, we recorded only 6-min walk test distance before versus after HSCT.

Results: The patients underwent transplantation at a median of 6 years post-diagnosis. All were engrafted and had a full or mixed chimerism. Enzyme levels were within normal ranges. Walking tests of all evaluable patients improved at a median 9-month follow-up.

Conclusion: HSCT aims to improve the disease and provides a permanent solution at the enzyme level, eliminating enzyme replacement therapy. Our study showed that HSCT, a less expensive and permanent treatment option, should be offered to patients with MPS VI.