Demyelinating disorders in children and adolescents: ADEM, optic neuritis and MODAG

The paper describes the case of a 4-year-old girl who presented with an episode of ADEM and, 8 years later, multiple relapses associated with optic neuritis. The patient resulted positive to anti-MOG antibodies. About a third of patients with an ADEM event may present: a) a second demyelinating event, which, depending on the clinical characteristics, may lead to the definition of multiphasic ADEM (in which the relapse occurs at least one month after the acute phase); b) ADEM-ON (ADEM-Optic Neuritis), in which after the first episode the demyelinating relapses interest the optic nerve or Multiple Sclerosis (MS). MOG antibody-associated disorders (MOGADs) define a sub-group of CNS inflammatory-acquired demyelinating syndromes distinct from MS, and aquaporin-4 (AQP4) positive neuromyelitis optica spectrum disorder (NMOSD), typically including CNS clinical syndromes such as ADEM, optic neuritis, transverse myelitis, and AQP4-seronegative NMOSD. The first-line of treatment commonly recognized in the acute phase is IV corticosteroids in high-dose or IV immunoglobulins. In case of relapse, the drug with evidence of efficacy is rituximab; other choices are immunosuppressive therapies, in particular azathioprine and mycophenolate. Eculizaumb is specifically indicated in forms of optic neuromyelitis in patients with ab anti-AQP4 positivity.