Coexistence of CSF anti-Ma2 antibody and 14-3-3 protein: a diagnostic dilemma between autoimmune encephalitis and Creutzfeldt-Jakob disease, a Case Report

Anti-Ma2 antibody encephalitis is a type of encephalitis associated with autoantibodies targeting intracellular antigens. Previous studies have detected the presence of 14-3-3 protein in some cases of AE associated with antibodies against neuronal surface antigens. This is the first report of concomitant anti-Ma2 antibody and CSF 14-3-3 protein positivity, which is a further extension of previous studies. This case demonstrates that CSF 14-3-3 protein positivity does not preclude AE and may reflect secondary neuronal injury. When both antibodies are present simultaneously, the diagnosis should be made in combination with the patient's imaging features, prion-specific testing and high titers of antineuronal antibodies to avoid delay in treatable disease.