Objective:

This study sought to determine the effects of rituximab on brain volume loss and expanded disability status scale (EDSS) in a cohort of pediatric patients with relapsing remitting multiple sclerosis (RRMS).

Background:

Childhood onset RRMS may limit age dependent primary brain growth, lead to brain atrophy and possibly early onset neurodegeneration. Primary goals of disease modifying therapy (DMT) are to reduce neuroinflammation and neurodegeneration.   

Design/Methods:

Retrospective review of pediatric RRMS patients who underwent MRI before and after rituximab was performed. Quantitative neuroimaging analysis was performed using FreeSurfer to segment and quantify grey and white matter volumes. EDSS data was recorded for clinical visits nearest the time of the respective MRIs.  

Results:

Twelve patients met inclusion criteria. Mean ages at initial and follow-up MRI were 15.1 and 17.6 years, respectively. Mean interval between initial and follow up MRI was 2.5 years. Mean duration of rituximab therapy at time of follow up MRI was 2.4 years. Total cortical grey matter changed by a mean of -1.8% (range -6.8 to +4.5%, annualized mean change of -0.62%). Subcortical gray matter volume changed by a mean of -2.6% (range -6.2% to + 3.9%, annualized mean change of -2.02%). Total cerebral white matter volume changed by a mean of -2.45% (range -8.6% to +7.7%, annualized mean change of -1.11%). EDSS decreased in all patients with a score greater than 0 with the exception of one patient with a stable score of 1.5. One patient did not have a recorded EDSS. 

Conclusions:

Pediatric patients with RRMS treated with rituximab exhibit volume loss in total cortical grey matter, subcortical grey matter and white matter. Further studies are needed in a larger cohort of patients to better understand the significance and clinical relevance of this treatment regimen compared to others especially in light of stable or improved EDSS in this cohort.