Disease course and outcome of acute disseminated encephalomyelitis is more severe in adults than in children

Background: Acute disseminated encephalomyelitis (ADEM) affects children more frequently than adults. Current studies investigating ADEM in different age groups are difficult to compare.

Objective: To investigate whether the clinical presentation, outcome and disease course of ADEM differ between adults and children.

Methods: Disease characteristics of 25 adults and 92 children suffering from ADEM between 1988 and 2008 were compared.

Results: The most common presenting symptoms of ADEM in both groups were pyramidal signs and encephalopathy. Ataxia occurred more frequently in children (p = 0.002). In general, MRI showed ill-defined and large white matter lesions in both groups, whereas periventricular lesions were more prevalent in adults (p = 0.001). In adults, duration of hospitalization was longer (p = 0.002) and intensive care unit (ICU) admission was more frequently required (p = 0.043). Three adults (12%) and one child (1%) died (p = 0.030). Fewer adults had complete motor recovery after their first clinical event (p <0.001). In 73 patients follow-up time was >= 2 years and most of these patients remained monophasic. Although relapses after ADEM can occur, only one adult (5%) and five children (6%) converted to MS.

Conclusions: The clinical presentations in children and adults share similarities, but the disease course and outcome of ADEM is more severe in adults with respect to hospitalization, ICU admission, recovery and mortality.