Acute Disseminated Encephalomyelitis (ADEM)

A previously well child becomes unsteady, weak or visually impaired over hours to days, then becomes unusually drowsy or behaviourally changed several days to weeks after an infection. That combination—new neurological deficits in more than one CNS location plus encephalopathy—should make ADEM a serious consideration. It is not, however, a diagnosis to make before excluding meningitis, herpes simplex encephalitis and other causes of acute encephalopathy. The first nursing question is not “Does the MRI look like ADEM?” It is “Is the airway protected, and is this child becoming less responsive, seizing or developing raised intracranial pressure?” Stabilization and empiric treatment for suspected CNS infection proceed while MRI, CSF and antibody testing refine the diagnosis.