Autoimmune Encephalitis in Late-Onset Seizures: When to Suspect and How to Treat

Epilepsy and epileptiform activity in late-onset Alzheimer disease: clinical and pathophysiological advances, gaps and conundrums

A growing body of evidence has demonstrated a link between Alzheimer disease (AD) and epilepsy. Late-onset epilepsy and epileptiform activity can precede cognitive deterioration in AD by years, and its presence has been shown to predict a faster disease course. In animal models of AD, amyloid and tau pathology are linked to cortical network hyperexcitability that precedes the first signs of memory decline. Thus, detection of epileptiform activity in AD has substantial clinical importance as a potential novel modifiable risk factor for dementia. In this Review, we summarize the epidemiological evidence for the complex bidirectional relationship between AD and epilepsy, examine the effect of epileptiform activity and seizures on cognition in people with AD, and discuss the precision medicine treatment strategies based on the latest research in human and animal models. Finally, we outline some of the unresolved questions of the field that should be addressed by rigorous research, including whether particular clinicopathological subtypes of AD have a stronger association with epilepsy, and the sequence of events between epileptiform activity and amyloid and tau pathology.

Coexistence of multiple anti-neuronal antibodies in autoimmune encephalitis in China: A multi-center study

Background

Given that the combination of multiple antibodies in autoimmune encephalitis (AE) is rare and its clinical significance is unclear, this study aimed to investigate the clinical characteristics and significance of overlapping multiple anti-neuronal antibodies in patients with AE.

Methods

We conducted a retrospective analysis of the clinical characteristics, treatment, and prognostic details of 22 patients with multiple coexisting antibodies from multiple clinical centers in China.

Results

Among the 276 patients who were AE antibody-positive, 22 (7.97%) had two or more antibodies. Among the 22 patients with coexisting AE-related antibodies, 14 patients (63.63%) were combined of cell surface and intracellular antibody, and the remaining 8 patients (36.36%) were detected to be cell surface antibody positive only. The main symptoms of the 22 patients in this cohort included fever, seizures, memory impairment, cognitive decline, and sleep disorders. Five (22.73%) patients had tumors, among whom four had small-cell lung cancers, and one had mediastinal tumors. A total of 20 patients were treated with steroids and intravenous immunoglobulin, and 18 showed varying degrees of symptomatic improvement after first-line immunotherapy. Three patients died of tumor progression or chemotherapy complications.

Conclusion

The coexistence of multiple anti-neuronal antibodies in patients with AE may cause a superimposition and diversification of clinical manifestations. Combined paraneoplastic antibody positivity may be suggestive of an underlying malignancy.

Drug-resistant epilepsy at the age extremes: Disentangling the underlying etiology

The incidence of epilepsy is highest at the extreme age ranges: childhood and elderly age. The most common syndromes in these demographics - self-limited epilepsies of childhood and idiopathic generalized epilepsies in pediatric age, focal epilepsy with structural etiology in older people - are expected to be drug responsive. In this work, we focus on such epilepsy types, overviewing the complex clinical background of unexpected drug-resistance. For self-limited epilepsies of childhood and idiopathic generalized epilepsies, we illustrate drug-resistance resulting from syndrome misinterpretation, reason on possible unexpected courses of epilepsy, and explicate the influence of inappropriate treatments. For elderly-onset epilepsy, we show the challenges in differential diagnosis possibly leading to pseudoresistance and analyze how drug-resistant epilepsy can arise in stroke, neurocognitive disorders, brain tumors, and autoimmune encephalitis. In children and senior people, drug-resistance can be regarded as a hint to review the diagnosis or explore alternative therapeutic strategies. Refractory seizures are not only a therapeutic challenge, but also a cardinal sign not to be overlooked in syndromes commonly deemed to be drug-responsive.

Clinical features and outcomes of leucine-rich glioma-inactivated protein 1 and contactin protein-like 2 antibody-associated autoimmune encephalitis in a Chinese cohort

The present study aimed to investigate the clinical manifestations, epidemiological characteristics, and outcomes of Chinese patients with voltage-gated potassium channel complex (VGKC) antibody-associated encephalitis. Patients diagnosed with VGKC antibody-associated encephalitis at our institution between January 2016 and December 2020 were included in this study. We retrospectively evaluated their clinical features, auxiliary examination results, treatments details, long-term outcomes, and risk factors for poor outcome. Of the 91 included patients, 61 (67.78%) were men and 30 (32.97%) were women. The most common clinical symptoms were seizures (n = 63, 69.23%), memory deficits (n = 62, 68.13%), mental behavioral disorders (n = 29, 31.87%), and hyponatremia (n = 57, 62.64%). Although patients with anti- leucine-rich glioma-inactivated 1 (LGI1) (n = 76) and anti- contactin-associated protein-like 2 (CASPR2) encephalitis (n = 15) had similar clinical manifestations, the former were more diverse. In total, 86 (94.51%) patients were treated with immunotherapy. Over a median follow-up period of 25 months, there were no mortalities and 14 (15.38%) patients experienced a relapse. Univariate analysis indicated differences in sex, modified Rankin Scale scores at onset, movement disorders, central hypoventilation, and intensive care unit occupancy between the good- and poor- outcome groups. Patients with anti-LGI1 and anti-CASPR2 encephalitis showed similar clinical manifestations while presenting delineating characteristics. Those with VGKC antibody-associated diseases generally responded well to immunotherapy and demonstrated favorable clinical outcomes. Several factors affected the prognosis, and a long-term follow-up examination is necessary.