AUTHOR=Wang Shan , Wang Jirui , Li Baizhu , Hu Ning , Jin Yingbin , Han Shiyu , Shang Xiuli 

TITLE=Case Report: Paroxysmal weakness of unilateral limb as an initial symptom in anti-LGI1 encephalitis: a report of five cases

JOURNAL=Frontiers in Immunology

VOLUME=Volume 14 - 2023

YEAR=2023

URL=https://www.frontiersin.org/journals/immunology/articles/10.3389/fimmu.2023.1191823

DOI=10.3389/fimmu.2023.1191823

ISSN=1664-3224

ABSTRACT=Anti-leucine-rich glioma-inactivated 1 (LGI1) encephalitis is the second most common kind of autoimmune encephalitis following after anti-N-methyl-d-aspartate receptor (NMDAR) encephalitis. Anti-LGI1 encephalitis is characterized by cognitive impairment or rapid progressive dementia, psychiatric disorders, epileptic seizures, faciobrachial dystonic seizures (FBDS) and refractory hyponatremia. Recently, we found an atypical manifestation of anti-LGI1 encephalitis, herein we describe five cases of anti-LGI1 encephalitis with paroxysmal limb weakness as an initial symptom. They had the similar presentation, sudden weakness involving unilateral limb was observed, which lasted approximately seconds and occurred dozens of times each day, with the positive for anti-LGI1 antibody in both serum and cerebrospinal fluid (CSF). FBDS occurred after a mean of 12 days following paroxysmal limb weakness in 3 of 5 patients (case 1, 4, 5). All patients were given high-dose steroid therapy which had a good effect on their condition. Based on this report, we interpreted the paroxysmal unilateral weakness may be a special pilepsy and have a relationship with FBDS. As an unusual neurological presentation, paroxysmal weakness can enrich the clinical manifestations of anti-LGI1 encephalitis, can help to raise awareness of the recognition of anti-LGI1 encephalitis in patients with this symptom, leading to early diagnosis and early treatment which contribute to improve clinical outcomes.