Anti-seizure related 6 homolog like 2 antibody-associated encephalitis:two cases report and literature review
CHENG Na
LU Yi-zhou
CHEN Sheng
ZHOU Qin-ming
Abstract：Objective To report and analyze clinical features of anti-seizure related 6 homolog like 2(SEZ6L2)antibody-associated encephalitis,and review relevant literatures.Methods and Results Two patients were all diagnosed and treated by Ruijin Hospital,Shanghai Jiaotong University School of Medicine from January 2022 to July 2024.The clinical manifestations were mainly with ataxia,gait abnormalities,cognitive dysfunction and bradykinesia.One case exhibited dysautonomia.Cerebrospinal fluid(CSF)white cell counts were elevated,and both serum and CSF antibodies related to autoimmune encephalitis were negative.Further testing for anti-SEZ6L2 antibody revealed that CSF and(or)serum were positive.MRI showed cerebellar atrophy,while 18F-DPA714 PET/MRI indicated abnormal increased uptake in the cerebellum.18F-FDG PET did not reveal any malignant tumors,however,one case showed decreased metabolism in the cerebellum,frontal lobe and temporal lobe.The clinical diagnosis was anti-SEZ6L2 antibody-associated encephalitis,and after immunotherapy,the symptoms improved.Conclusions Anti-SEZ6L2 antibody-associated encephalitis is rare,and it has complicated clinical manifestations.There are difficulties in the early diagnosis and differential diagnosis,but early immunomodulatory treatment leads to a good prognosis in some patients.
Keywords：EncephalitisAutoimmune diseasesAutoantibodiesSEZ6L2(not in MeSH)
Publication Date：2025-12-25
Online Publishing Date：2026-01-23(First online date of this platform, not the publication date of the document)
Pages：7( 1150-1156 )