Clinical and radiological features of recurrent demyelination following acute disseminated encephalomyelitis (ADEM)

Abstract

Objective: To identify clinical and radiological features of children that relapse following an initial presentation of acute disseminated encephalomyelitis (ADEM).

Methods: Clinical records and neuroimaging of children under the age of 16 years presenting with ADEM to a pediatric neurology referral center between 2006 and 2010 were evaluated.

Results: Of the 32 children with ADEM, 24 (7 female) with a median age of 4.8 (range 3-15) had a monophasic course. Eight patients (25%; 4 female) with median age of 6.9 (range 3-16) had relapsing demyelination; 3 relapsing within the 3 month interval (still defined within a monophasic event); 4 with multiphasic disseminated encephalomyelitis (MDEM), and 1 with non-multiple sclerosis recurrent demyelination. Clinical features at presentation could not distinguish the monophasic from the relapsing group. Infratentorial imaging changes (brain stem and cerebellar) were seen more frequently in the relapsing group (8/8 vs. 20/24), although differences were not statistically significant. At relapse, seven of the eight patients had clinical and radiologic infratentorial syndromes involving brainstem and/or cerebellum. Only one patient had more than one relapse. After a median follow up of 27 months (range 0-96) across the whole group, no patients were diagnosed with multiple sclerosis.

Conclusions: ADEM patients with infratentorial demyelination are more likely to present with a second infratentorial demyelination, although clinical and radiological features at outset could not predict the relapsing cohort.

Keywords: ADEM; Acquired demyelination syndrome; Demyelination; Multiple sclerosis; Relapsing.