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.
There has been an explosion in our knowledge of autoimmune encephalitis associated with antibodies to neuronal cell surface antigens, and two of the most common forms, anti-NMDA receptor encephalitis and anti-LGI1encephalitis, are typically associated with distinctive clinical features.
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.
We had two cases with anti-LGI1encephalitis, that is, one with sleep disorder onset, and the other one with seizure onset, both of whom recovered after treatment.
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.
Treatment outcomes were assessabled in 103 patients (10 patients died or withdrew), including anti-GABA<sub>B</sub>R encephalitis (11), anti-LGI1encephalitis (16), anti-NMDAR encephalitis (73), Caspr2 antibody encephalitis (3).
Thus, in order to elucidate the structure-function relationship and contribution of hippocampal subfields to pattern separation, we examined patients (n = 15, age range: 36-77 years) with the rare LGI1encephalitis showing lesions to hippocampal subfields.
Then, we focus on several antibody-mediated encephalitis disorders that associate with seizures and review the synaptic alterations caused by patients' antibodies, with emphasis on those that have been modeled in animals (e.g., antibodies against NMDA, AMPA receptors, LGI1 protein) or in cultured neurons (e.g., antibodies against the GABAb receptor).
With the limitations imposed by the low number of cases, differences to published adult cohorts included: absence of faciobrachial dystonic seizures and hyponatremia in patients with LGI1-positive encephalitis; slightly higher proportion of isolated epilepsy syndromes in CASPR2-positive patients; absence of tumour in the whole cohort.
This review will focus on the current state of knowledge on N-methyl-D-aspartate (NMDA) receptor-associated encephalitis and limbic encephalitis, the latter predominantly involving antibodies against the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor, the γ-aminobutyric acid (GABA)B receptor and leucine-rich glioma-inactivated 1 (LGI1) protein.
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.
We report a rare case of an elderly gentleman who was found to have thymoma-associated myasthenia gravis and LGI1-encephalitis with myokymia, who presented with nephrotic syndrome (minimal change glomerulopathy) after thymectomy.
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.
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.
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.