[Clinical outcome of the hyperacute form of acute disseminated encephalomyelitis]

Acute disseminated encephalomyelitis (ADEM) is an inflammatory disease that damages the white matter of the central nervous system. Its clinical course is monophasic and multifocal. The outcome is usually favourable. We report our experience in the management of the hyperacute form of ADEM.

A retrospective chart review was performed on five patients admitted in coma with a diagnosis of ADEM in the Paediatric Intensive Care Unit (PICU). We describe their epidemiological, clinical, microbiological, magnetic resonance imaging features and their treatment and outcomes.

The mean age was 5.2 years and all were male. None of them fulfilled radiologic criteria for acute haemorrhagic leukoencephalitis. At admission all patients were in a coma, and all were on controlled mechanical ventilation support. Before their admission all patients had fever. In all cases the time between the first neurological symptom and coma was ≤ 24hours. The cerebrospinal fluid examination was abnormal in three patients, and in one case, oligoclonal bands were detected. The first brain magnetic resonance imaging (MRI) showed white matter and basal ganglia lesions in all patients, and in three cases the spinal medulla was affected by demyelination. All patients were treated with a course of high-dose methylprednisolone. Four patients were also treated with high-dose immunoglobulins, and one of them received plasmapheresis. Two patients died, and one patient had severe sequelae at discharge from the PICU. At discharge the lesions in the white matter were still present in the MRI. After nine months the three survivors had a Glasgow Outcome Scale score of five and no one relapsed.

There is a hyperacute clinical form of ADEM which has a high mortality rate. In the short term, the clinical improvement of hyperacute ADEM is not accompanied by a decrease of severity of the brain MRI.