Pediatric-onset multiple sclerosis (POMS) Multiple Sclerosis (MS), a chronic inflammatory autoimmune disease of the CNS, commonly diagnosed in young adults, but can also affect children Clinical onset before the age of 18 (16) years Incidence of 0.5 and 1.66 /100 000 children. Between 3 and 10% of MS >16 years and < 1% under 10 years of age Focal or multifocal acute demyelinating presentation CNS: central nervous system