Anti leucine-rich glioma inactivated 1 (LGI1) encephalitis is a rare autoimmune encephalitis (AE), characterized by acute or subacute cognitive impairment, faciobrachial dystonic seizures, psychiatric disturbances and hyponatremia.
Anti-LGI1encephalitis was associated with the DRB1*07:01-DQB1*02:02 haplotype (10 patients; 91%) in HLA class II genes, as well as with B*44:03 (8 patients; 73%) and C*07:06 (7 patients; 64%) in the HLA class I region.
Antibodies against the N-methyl, d-aspartate receptor (NMDAR) and leucine-rich glioma inactivated 1 (LGI1) are the commonest autoantibodies known in patients with autoimmune forms of encephalitis.
Autoimmune forms of encephalitis have been associated with autoantibodies against synaptic cell surface antigens such as NMDA- and AMPA-type glutamate receptors, GABA(B) receptor, and LGI1.
Drug-resistant seizures are common in patients with leucine-rich, glioma-inactivated 1 (LGI1)-IgG associated and contactin-associated protein-like 2 (CASPR2)-IgG associated encephalitis.
Eleven of the 13 LGI1-antibody encephalitis patients (84.6%) showed asymmetrical FDG high uptake in the hippocampus: nine (81.8%) on the left hippocampus and two (18.2%) on the right.
Initial manifestation of psychiatric symptoms in patients with anti-LGI1encephalitis may be a poor prognostic factor, at least in the short term, in that it misleads both the patients and the clinicians to neglect the typically accompanied symptoms of the disease such as faciobrachial dystonic seizure, delaying the timing of immune therapy.
Multiple frequent seizure semiologies, in addition to numerous subclinical seizures and interictal epileptiform discharges, are hallmarks of LGI1-antibody encephalitis.
Patients with anti-LGI1encephalitis had incomplete recovery with significant and persisting verbal (mean [SE] Rey Auditory Verbal Learning Test [RAVLT], delayed recall: patients, 6.52 [1.05]; controls, 11.78 [0.56], P < .001) and visuospatial (Rey-Osterrieth Complex Figure Test [ROCF], delayed recall: patients, 16.0 [1.96]; controls, 25.86 [1.24]; P < .001) memory deficits.
Some specific phenomenology of movement disorders are likely to give clue about the type of antibody, for instance, presence of paroxysmal dystonia (facio-brachial dystonic seizures) are a pointer toward presence of LGI-1 antibodies, and orofacial lingual dyskinesia is associated with NMDAR associated encephalitis.
The methods utilized in this study were prospective analysis of the clinical manifestations, types of seizures, electroencephalogram (EEG), adjuvant examination, treatment and prognosis of 19 cases of LGI1-antibody encephalitis diagnosed from January 2017 to February 2018 in First Affiliated Hospital of Zhengzhou University, and reviewed related literatures.