Polyradiculitis in autoimmune encephalitis: a case report and review

Abstract

Background: Limbic encephalitis is a subacute progressive disorder characterized by disturbances in memory and behavior along with seizures. Antibodies against leucine-rich glioma-inactivated 1 (LGI1) are associated with a subtype of encephalitis which along with the abovementioned symptoms is also characterized by severe pain and autonomic dysfunction. The classical radiological presentation of LGI1 encephalitis is that of amygdala and hippocampal enlargement unilaterally or bilaterally with a T2 hyperintensity. Extratemporal involvement is considered a rare feature. Case description: We present the only known case in our knowledge of anti-LGI1 encephalitis in a 47-year-old male presenting as dorsal root ganglia and spinal nerve enhancement on imaging. Discussion: Clinicians should be aware of this atypical presentation and consider anti-LGI1 encephalitis as a possible diagnosis when presented with such a neuroradiological feature.