Myelin Oligodendrocyte Glycoprotein Antibodies in Breast Milk in a Lactating Woman With Severe Enterovirus-Associated MOGAD

OBJECTIVES: Myelin oligodendrocyte glycoprotein antibody (MOG-IgG)-associated disease (MOGAD) is a distinct neuroinflammatory disorder, which may be preceded by infections. Transmission of MOG-IgG from blood into breast milk has not been reported previously. METHODS: We present the case of a 38-year-old lactating woman with a severe manifestation of MOGAD after enterovirus gastroenteritis, who was still lactating at that time. Alongside with detailed clinical characteristics, we measured MOG-IgG in breast milk and serum from the breast-fed infant. RESULTS: Our patient experienced a severe progressive episode of CNS inflammation, affecting the optic nerve, brain, and spinal cord, before which she was partially breastfeeding. Her condition rapidly worsened to coma with status epilepticus, requiring intensive care admission. High serum MOG-IgG titers were detected and prompt attack therapy initiated with high-dose glucocorticosteroids followed by plasma exchange, which led to rapid clinical improvement. The patient's breast milk tested positive for MOG-IgG, whereas the serum of the breastfed infant was negative. DISCUSSION: Early diagnosis and therapeutic intervention at acute onset of MOGAD is important for attack remission. MOG-IgG may be detected in breast milk of lactating woman with MOGAD, but is probably not transmitted to the infant in detectable quantities.