ABSTRACT
Objective To evaluate the clinical and paraclinical features of Chinese patients with anti- LGI1 encephalitis. Methods Patients with memory deficits, psychiatric symptoms, seizures or altered level of consciousness, suspicious of encephalitis, at presentation to Peking Union Medical College Hospital were recruited between July 2013 and January 2018, and tested for anti-LGI1 antibodies in their serum and/or cerebrospinal fluid(CSF) samples. Patients with anti-LGI1 antibodies were enrolled. The demographic characteristics, clinical manifestations, laboratory examination results, neuroimaging features, immunotherapy, follow-up practices and outcomes for included patients were registered and analyzed. Results The study enrolled 120 patients, of whom 66.7% were male. The median age was 61 years (interquartile range [IQR]: 49-66 years). Seizures(65.0%) were the most common initial symptoms. Most patients developed seizures (95.0%), including faciobrachial dystonic seizures (54.2%), memory deficits (92.5%), and psychiatric symptoms (69.1%). Brain MRI and 18F-FDG PET / CT showed that the lesions were mainly located in unilateral or bilateral medial temporal lobes, and (or) basal ganglia. Of the patients, 95.0% received intravenous immunoglobulin (IVIg) or corticosteroids, 47.5% received mycophenolate mofetil as long-term immunotherapy, and no one received second-line immunotherapy. The median follow-up was 34.2 months(IQR: 22.0-45.6 months). 91.2% had a good outcome (modified Rankin Scale score≤2 points). Residual mild memory deficits were present in 47.8% of the patients. Nine deaths were documented. Relapses occurred in 24.8% of the patients in the first year. In total, 24 (20%)cases were young patients(onset age ≤45 years).There were fewer males among the younger patients(37.5% vs. 74.0%, P < 0.01). Besides, there were fewer younger patients with psychiatric symptoms(50.0% vs. 74.0%, P=0.02), hyponatremia(33.3% vs. 68.8%, P < 0.01), and abnormalities on brain 18F-FDG PET/CT(20.8% vs. 47.9%, P=0.02). The relapse-free survival rate was significantly higher in the young patients. Conclusions Elderly males were predominant in patients with anti-LGI1 encephalitis. Most patients developed symptoms of limbic encephalitis and/or FDBS during the disease course. Several patients were young adults and lacked typical symptoms. Neuroimaging features were consistent with the involvement of limbic system or basal ganglia. Patients with anti-LGI1 encephalitis respond well to immunotherapy, irrespective of the age.
ABSTRACT
RESUMEN Introducción: La encefalitis asociada a anticuerpos dirigidos contra la proteína 1 inactivada del glioma rica en leucina (LGI1) es una entidad poco frecuente de inicio subagudo que se caracteriza clínicamente por la presencia de alteraciones cognitivas, alteraciones conductuales y crisis epilépticas. El pronóstico en la mayoría de los casos es favorable, aunque son frecuentes los déficits amnésicos residuales. Caso clínico: Mujer de 76 años que comenzó de manera súbita con una serie de crisis tónico - clónicas generalizadas y posterior alteración del nivel de consciencia. Se inició tratamiento anticonvulsivante con discreta mejoría clínica. En la resonancia magnética realizada durante el ingreso se observó hiperintensidad en hipocampo izquierdo en secuencias T2 y T2-FLAIR. Ante la sospecha de encefalitis límbica autoinmune se inició tratamiento inmunomodulador con corticoesteriodes e inmunoglobulinas con mejoría clínica. Posteriormente se detectaron anticuerpos anti - LGI1 en líquido cefalorraquídeo. Conclusiones: La encefalitis autoinmune asociada a anticuerpos anti-LGI1 puede producir clínica neurológica variada y orden de instauración variable, incluso en ocasiones agudo. El tratamiento con inmunoterapia precoz es importante tanto para la mejoría clínica en la fase aguda como para el pronóstico a largo plazo.
Abstract Introduction: Leucine rich glioma inactivated protein 1 (LGI1) antibody encephalitis is a rare disease characterized by subacute memory impairment, behavioral disorders and epileptic seizures. Even most cases have a good outcome, residual cognitive deficits are common. Case report: 76-year-old woman who started with acute onset generalized tonic - clonic seizures and subsequent impaired level of consciousness. Antiepileptic treatment was started with slight clinical improvement. In magnetic resonance imaging performed during admission left hippocampal hyperintensity was seen in T2 and T2-FLAIR sequences. As autoimmune limbic encephalitis was suspected, immunomodulatory treatment with intravenous corticosteroids and immunoglobulins was started with clinical improvement. Afterwards, anti -LGI1 antibodies were positive in cerebrospinal fluid testing. Conclusions: anti - LGI1 antibody related encephalitis can produce different neurological manifestations and diverse onset, even acute. Early immunomodulatory treatment is important to improve both clinical manifestations and long - term outcome.