[P1-121] RAnti-aquaporin-4 antibody in a toddler; a real pathogenetic marker of the encephalitis?
[Introduction] Recently, the broader concept of neuromyelitis optica spectrum disorder has been introduced that includes the numerous neurologic symptoms in the context of AQP4 autoimmunity. We report a NMO antibody seropositive toddler who presents with acute encephalitis.
[Case Report] A13-month old boy presented to emergency room with first attack of febrile seizure and altered mentality during a febrile illness for two days. He was stuporous and showed right arm weakness after intractable recurrent tonic clonic seizures of right arm. Initial brain MRI and CSF studies were normal at the day of admission. Electroencephalography showed diffuse background suppression and stuporous mentality persisted. There was no evidence of infection or other autoimmune disease on comprehensive work up except sero-positivity of NMO antibody (1:480) in his serum. Follow-up brain and spine MRI at hospital day 7 showed diffuse cortical, subcortical T2/ FLAIR high signal intensities without spinal cord involvement. On the tentative diagnosis of autoimmune encephalitis, intravenous methylprednisolone was initiated and he became seizure-free and his mental status and motor weakness gradually improved. At one-year follow-up, he is free of seizure and can walk alone with mild right hemiparesis. The NMO antibody titer decreased serially and is not detected anymore.
[Conclusion] The NMO-seropositivity in this young age group is very rarely reported and the involved brain areas are not typical for the NMO. However, the clinical improvement with serial NMO titer decrement after steroid therapy can suggest the association of the NMO antibody in the pathogenesis of pediatric autoimmune encephalitis.
[Case Report] A13-month old boy presented to emergency room with first attack of febrile seizure and altered mentality during a febrile illness for two days. He was stuporous and showed right arm weakness after intractable recurrent tonic clonic seizures of right arm. Initial brain MRI and CSF studies were normal at the day of admission. Electroencephalography showed diffuse background suppression and stuporous mentality persisted. There was no evidence of infection or other autoimmune disease on comprehensive work up except sero-positivity of NMO antibody (1:480) in his serum. Follow-up brain and spine MRI at hospital day 7 showed diffuse cortical, subcortical T2/ FLAIR high signal intensities without spinal cord involvement. On the tentative diagnosis of autoimmune encephalitis, intravenous methylprednisolone was initiated and he became seizure-free and his mental status and motor weakness gradually improved. At one-year follow-up, he is free of seizure and can walk alone with mild right hemiparesis. The NMO antibody titer decreased serially and is not detected anymore.
[Conclusion] The NMO-seropositivity in this young age group is very rarely reported and the involved brain areas are not typical for the NMO. However, the clinical improvement with serial NMO titer decrement after steroid therapy can suggest the association of the NMO antibody in the pathogenesis of pediatric autoimmune encephalitis.