Myelin oligodendrocyte glycoprotein-antibody disease (MOGAD) with leukodystrophy-like presentation.

Myelin oligodendrocyte glycoprotein-antibody disease (MOGAD) is an immune-mediated demyelinating disorder, distinct from MS, which typically affects the optic nerve, spinal cord, brain and/or brainstem. Diffuse white matter involvement that resembles a leukodystrophy has been reported only in children. We present a woman aged 29 years with new right optic neuritis on a background of previously unexplained, longstanding, bilateral, reduced visual acuity. MR scan of the brain and orbits showed confluent, bilateral, posterior predominant white matter changes reminiscent of a leukodystrophy, along with bilateral optic atrophy. She was strongly MOG-seropositive. Positron-emission tomography scanning showed enlarged cervical lymph nodes, and biopsy found necrotising granulomata without tuberculosis. She showed a marked clinico-radiological response to corticosteroids, going from legally blind to functioning independently. Most strikingly, the chronically affected left eye improved significantly, 5 years after symptom onset. This expands the phenotypic spectrum of MOGAD as well as therapeutic expectations after a delayed presentation.