Acute disseminated encephalomyelitis, multiphasic disseminated encephalomyelitis and multiple sclerosis in children

Forty-eight children with disseminated demyelination of the CNS, 28 with ac ute disseminated encephalomyelitis (ADEM), seven with multiphasic dissemina ted encephalomyelitis (MDEM) and 13 with multiple sclerosis were studied fo r a mean follow-up period of 5.64 years. The presentation findings of the A DEM/MDEM group were compared with those of the multiple sclerosis group. Th e following findings were more commonly seen in ADEM/MDEM presentation comp ared with the multiple sclerosis presentations: predemyelinating infectious disease (74 versus 38%, P < 0.05); polysymptomatic presentation (91 versus 38%, P < 0.002); pyramidal signs (71 versus 23%, P < 0.01); encephalopathy (69 versus 15%, P < 0.002); and bilateral optic neuritis (23 versus 8%, no t significant). Seizures occurred only in the ADEM/ MDEM group (17 versus 0 %, not significant). Unilateral optic neuritis occurred only in the multipl e sclerosis patients (23 versus 0%, P < 0.01). There were no differences in the frequencies of transverse myelitis, brainstem involvement, cerebellar signs and sensory disturbance between the two groups. ADEM/MDEM patients we re more likely to have blood leucocytosis (64 versus 22%, P < 0.05), CSF ly mphocytosis (64 versus 42 %, not significant) and CSF protein elevation (60 versus 33%, not significant). Patients presenting with multiple sclerosis were more likely to have intrathecal synthesis of oligoclonal bands on pres entation (64 versus 29%, not significant). MRI showed that subcortical whit e matter lesions were almost universal in both groups, though periventricul ar lesions were more common in multiple sclerosis (92 versus 44%, P < 0.01) . By contrast, in ADEM/ MDEM there was absolute and relative periventricula r sparing in 56 and 78% of patients, respectively. Followup MRI revealed co mplete or partial lesion resolution in 90% and no new lesions in the ADEM/M DEM group. All of the multiple sclerosis patients had new lesions on repeat MRI (five during relapse and six during asymptomatic convalescent phases). The outcome in the ADEM patients was mixed; 57% of patients made a complet e recovery. The mean follow-up for the 35 ADEM/MDEM patients was 5.78 years (range 1.0-15.4 years). Eight of the 13 multiple sclerosis patients relaps ed within the first gear; 11 had a relapsing-remitting course, one a primar y progressive course and one a secondary progressive course. These differen ces in the presentation of ADEM/ MDEM compared with multiple sclerosis may help in the prognosis given to families regarding the possibility of later development of multiple sclerosis.