Pediatric Multiple Sclerosis: an Update.

PURPOSE OF REVIEW: Diagnostic criteria for pediatric-onset multiple sclerosis (POMS) and related demyelinating disorders have been updated, neuroimaging studies have revealed new insights, biological assays identify patients with specific antibodies that influence both diagnosis and treatment, clinical trials are informing on treatment efficacy and safety, and longitudinal studies of neurological, cognitive and quality of life outcomes are informing on the impact of these diseases. We provide updates to assist providers caring for these children. RECENT FINDINGS: The recent 2017 McDonald Criteria for MS provide a simplified means to confirm diagnosis at onset and over time, and have been shown to be equally applicable for POMS. MRI analyses demonstrate that brain volume is reduced at onset, and that both volumetric and tissue integrity measures decline over time, indicating that POMS shares the degenerative aspects that also characterize adult-onset disease. The presence of myelin oligodendrocyte glycoprotein (MOG) antibodies at onset is detected in more than 50% of children with acute disseminated encephalomyelitis. When persistent over time, they are associated with relapsing disease. The first randomized clinical trials of disease supports superiority of fingolimod over subcutaneous interferon beta 1a, and demonstrated a favorable safety profile. Finally, while Expanded Disability Status Scale (EDSS) scores remain low in the first 10 years post-onset, POMS is associated with high rates of patient-reported fatigue and reduced engagement in exercise and carries a risk for cognitive impairment. The past 15 years have borne witness to a marked expansion in recognition and research in POMS. There are now more specific diagnostic criteria, antibodies to CNS proteins appear to define diagnostically distinct disorders, clinical trials have successfully launched and one has completed, and we are gaining increasing appreciation of the impact of MS and related disorders on the lived experience of children and adolescents.