Early Effects after Hematopoietic Stem Cell Transplantation in 13 Children with Juvenile Metachromatic Leukodystrophy

Background: Hematopoietic stem cell transplantation (HSCT) is currently the only available treatment option for juvenile metachromatic leukodystrophy (MLD). While we previously identified predictors for long-term outcome, the aim of this work was to characterize the early course after HSCT to investigate the time course for the treatment effect.

Method: In all children with juvenile MLD transplanted since 2001 at the University Children’s Hospital of Tübingen, the motor function was tested using GMFM-88 and the cognitive function using FSIQ before and after HSCT. In addition, the cerebral changes were quantified by MRI score, demyelination load, brain volume, and MR spectroscopy.

Results: All 13 children were successfully transplanted without relevant complications. Mean follow-up after transplantation was 4.5 years (1–13.5 years). Children who lost motor function after HSCT deteriorated in the first months after HSCT (n = 6), while the rest remained stable during this period (n = 7) and did not show any relevant deterioration during the further observation period. FSIQ < 85 before HSCT was another predictor of a rapid deterioration after transplantation. HSCT did not affect the neuropathy. The correlation of the MRI parameters with the clinical course after HSCT will be shown.

Conclusion: As the HSCT takes up to 2 years to become neurologically effective, it appears relevant to understand when any possible deterioration occurs. Our data indicates that this might happen already early after HSCT, that is, HSCT might potentially trigger the deterioration. This underlines the importance of defining clear inclusion criteria for HSCT in MLD.

No conflict of interest has been declared by the author(s).