Autologous hematopoietic stem cell transplantation for pediatric multiple sclerosis: a registry-based study of the Autoimmune Diseases Working Party (ADWP) and Pediatric Diseases Working Party (PDWP) of the European Society for Blood and Marrow Transplant

Autologous hematopoietic stem cell transplantation for pediatric multiple sclerosis: a registry-based study of the Autoimmune Diseases Working Party (ADWP) and Pediatric Diseases Working Party (PDWP) of the European Society for Blood and Marrow Transplant
Approximately 5% of multiple sclerosis (MS) patients are diagnosed before 18 years. Pediatric onset is associated with an earlier disability than patients with adult onset and cognitive impairment is present in about 30%. Disease-modifying drugs are available but a relapsing course is frequent. While autologous hematopoietic stem cell transplantation (HSCT) has been investigated for decades in adults with promising results, there are only very few pediatric patients reported in the literature.
The retrospective multicenter study analyzed data from the European Bone Marrow Registry and identified 22 patients from 7 centers. Additional information was requested from the identified centers by questionnaires.
Data was available for 21 patients, who were included in the study. All patients had been treated with disease-modifying treatments prior to HSCT, 11 with more than one. 20 patients received anti-thymocyte globulin as part of their conditioning regimen. 18 patients had follow-up data available, 2 patients experienced clinical and MR-radiological relapse about two years after HSCT. Another patient was identified as having subclinical disease with enhancing lesions on MRI. 16 patients improved in their disability scores. All patients were alive at last follow-up and only one patient experienced serious HSCT-related complications (sepsis with ICU admission).
This study is limited as a small retrospective study. Follow-up data was not available for all and the median follow-up duration was only 2.8 years. There was no comparison group to relate the outcome after HSCT to a reference group of pediatric MS patients.
Autologous HSCT can be considered as a treatment option in pediatric-onset multiple sclerosis patients where first-line treatment was not effective. However, long-term outcome data are missing and therefore this treatment option still must be considered experimental.