AQP4-IgG-seropositive neuromyelitis optica spectrum disorder concurring with anti-N-methyl-D-aspartate receptor encephalitis at pediatric age: a case report

Objective: Neuromyelitis optica spectrum disorder (NMOSD) and autoimmune encephalitis with anti-N-methyl-Daspartate receptor (NMDA) receptor antibodies pose distinct autoimmune challenges, yet their clinical symptomatology can overlap.This study explores the combined occurrence of these conditions, recognizing the potential for intensified symptoms due to their shared immune system involvement.Case presentation: A rare case of an 8-year-old girl diagnosed with both disorders is presented.Initial treatment resulted in improvement, but a subsequent relapse required hospitalization.Laboratory, imaging, and clinical assessments supported the coexistence of NMOSD and autoimmune encephalitis associated with NMDA receptors.Considering the high risk of progression and incomplete response to conventional therapy, rituximab, a monoclonal antibody targeting B-lymphocytes, was administered, showing positive neurological dynamics.Conclusion: This case underscores the diagnostic challenges posed by overlapping features and emphasizes the importance of prompt antibody testing for accurate treatment and prognosis determination.Understanding the intricate relationship between NMOSD and autoimmune encephalitis is vital for tailored therapeutic approaches, shedding light on the complexity of autoimmune comorbidities in neurology.