LOS ANGELES – There’s substantially higher risk of relapse and epilepsy after acute disseminated encephalomyelitis when children present with serum antibodies against myelin oligodendrocyte glycoprotein, according to British investigators.
“Traditionally, we told parents that ADEM [acute disseminated encephalomyelitis] is typically monophasic. I do tell parents now that theif we see” myelin oligodendrocyte glycoprotein antibodies (MOG-Ab), said senior investigator Yael Hacohen, MBBS, DPhil, a pediatric neurology lecturer at University College London.
There was also a strong trend for relapsing disease when children presented with seizures, and an increased risk of post-ADEM epilepsy with oligoclonal bands on cerebrospinal fluid analysis, a marker of inflammation.
ADEM is an acute CNS demyelinating disorder primarily affecting young children, often after upper respiratory tract infections and occasionally after measles, mumps, and rubella vaccination. Signs can include limb weakness, stumbling, and coma. Many children recover without incident, but some don’t.
There’s been an increasing number of reports of children – and adults – presenting with antibodies against MOG, a glycoprotein on the outermost layer of the myelin sheath. Its exact function is unknown, but antibodies have been found in a number of inflammatory CNS conditions, and its role in pathogenesis is being explored. Testing is available for clinical use, but it isn’t standardized. For now, titer levels aren’t being used to guide treatment at University College London, Dr. Hacohen said at the American Academy of Neurology annual meeting.
The team reviewed 74 children with ADEM who presented at three pediatric neurology centers during 2005-2017, at a median age of 4.5 years. There were about equal numbers of boys and girls, and all had MRI abnormalities consistent with ADEM. Fifty children (68%) were MOG-ab positive.