Anti-MOG positive pediatric cases with diverse clinical spectrum in demyelinating disorders

Abstract

Myelin oligodendrocyte glycoprotein (MOG) is a protein expressed on the outer surface of oligodendrocytes and myelin sheath in the central nervous system (CNS). It has been identified as an candidate autoantibody target in inflammatory demyelination disease. Autoantibodies against MOG predominantly in children are related to multiple sclerosis(MS), acute disseminated encephalomyelitis(ADEM), neuromyelitis optica spectrum disorder(NMOSD) and relapsing optic neuritis(ON) Here we report three cases who had anti-MOG antibody positive with distinctive clinical features. Case 1 was a 6-year- old girl who was presented with similiar attacks of encephalopathy, gait disturbance.She was diagnosed as multiphasic ADEM with bilateral patchy T2–flair hyperintensity on cranial magnetic resonance imaging( MRI). She responded to the combination of low-dose steroid and AZA treatment ; the number of attacks was significantly decreased. Case 2 was a 13-year-old boy who was presented with left visual loss. His neurological examination was normal except pale left optic disc. Orbital MRI revealed T2 hyperintensity and gadolinium enhancement of left optic nerve. AQP-4 antibody was negative, he was recovered completely with the steroid treatment. After the two years he was admitted with blurred vision on the other eye. He was diagnosed as recurrent ON as his orbita MRI showed ON. His anti-MOG antibody which analyzed at the second attack was positive. Case 3 was a 5-year-old girl who was presented with ascendent weakness. She was diagnosed as pediatric acute myelitis with T2 hyperintensity from medulla oblongata to sixth thoracal level on her MRI. Two months later, she was presented with back pain while steroid treatment was tapering. MRI showed T2 hyperintensity between T8-T12 levels. She was diagnosed with NMOSD. She was treated with the azathioprine after the second attack. We intend to emphasize that MOG antibody should be searched in pediatric demyelinating disorders and its positivity may reflect diverse clinical spectrums.