Anti-LGI1 encephalitis: A family affair.

Here we describe the second ever-reported case of familial anti-leucine-rich glioma-inactivated protein 1 (LGI1) limbic encephalitis (LE). Two elderly Caucasian sisters presented with psychiatric symptoms and cognitive impairment, followed by faciobrachial dystonic seizures. Anti-LGI1 antibodies were detected in their serum. Considering they had been living in distant regions for decades, environmental factors could be ruled out. Human leukocyte antigen (HLA) genotyping revealed that both carried HLA-DRB107, found in 90% of anti-LGI1 encephalitis patients, HLA-DQA102:01 and HLA-DQB103:03, commonly associated with DRB107:01. Considering the exceptional nature of familial cases, as-yet-unknown genetic contributors other than HLA might play a role in our siblings.