Antibodies to native myelin oligodendrocyte glycoprotein (nMOG) in 47 children during a first episode of CNS demyelination (acute disseminated encephalomyelitis [ADEM] in 19, and a clinical isolated syndrome [CIS] in 28) were investigated by a cell-based bioassay in a study at Children’s Hospital at Westmead, Sydney, Australia, and at the University of Munich, Germany. High serum immunoglobulin G (IgG) titers to nMOG were found in 40% children with CIS/ADEM and in 0% of control children with other neurologic disorders, in healthy children, or in adults with inflammatory demyelinating diseases. In contrast, IgM antibodies to nMOG occurred in only 3 children affected by ADEM. Children with high anti-nMOG IgG titer were significantly younger than those with low IgG titer. Anti-nMOG IgG titers were similar in CIS and ADEM groups, and did not predict conversion from CIS to MS during a mean 2-year follow-up. Intrathecal IgG-anti-MOG antibody synthesis occurred only in the CIS group. nMOG is a major target of the humoral immune response in a group of children with inflammatory diseases of the CNS. 
COMMENT. In adults, a first CNS demyelinating event is most likely to be MS, whereas in children, ADEM is more frequent, with a lower risk of progression to MS. Another first demyelinating event in children is a clinically isolated syndrome (CIS) with a higher risk of MS. The above study demonstrates a specific antibody response to nMOG in a subgroup of children with a first demyelinating event but not in adults with demyelinating disease.
MRI characteristics of children and adults with pediatric-onset MS . Pediatric onset MS has a greater MRI disease burden both early on in the disease and later, with higher frequency of relapses than in adult onset MS. Children with early onset MS showed a higher T1 lesion volume compared with adults with similar disease duration. Disease is more aggressive in early stages of childhood MS, but disability is slower to accrue in pediatric-cf adult-onset MS.
MRI Barkhof criteria were predictive of conversion to MS in 42% of 468 patients with a clinically isolated syndrome, irrespective of interferon treatment for 1 year. At least 9 T2-weighted lesions and at least 3 periventricular lesions at baseline were the Barkhof criteria with the strongest prognostic value. Follow-up MRI was most informative after 9 months. 
Barkhof MRI criteria predict early relapse in pediatric MS. At least 3 of 4 Barkhof criteria at onset were predictive of early relapse in 20 (71%) of 28 children with MS onset before age 16 years.