Clinical characteristics, long-term functional outcomes and relapse of anti-LGI1/Caspr2 encephalitis: a prospective cohort study in Western China

Abstract

Objective: To study the clinical characteristics of anti-leucine-rich glioma-inactivated 1 (LGI1) encephalitis and anti-contactin-associated protein-like 2 (Caspr2) encephalitis and to investigate factors associated with poor long-term neurological functional outcomes and relapse among patients in western China. Methods: In this single-center prospective cohort study, we consecutively enrolled patients with anti-LGI1 encephalitis and anti-Caspr2 encephalitis from April 2014 to February 2021. Patient outcomes were assessed using the modified Rankin scale. Predictors of long-term functional outcomes and relapse were analyzed. Results: Forty-four anti-LGI1 encephalitis patients [median age: 44 years, range: 18–82 years; females: 25 (56.8%)], 35 anti-Caspr2 encephalitis patients [median age: 43 years, range: 14–80 years; females: 19 (54.3%)], and 5 dual-positive patients [median age: 44 years, range: 36–58 years; females: 5 (100%)] were enrolled. Overall, 86.4% anti-LGI1 encephalitis patients and 80% anti-Caspr2 encephalitis had a favorable neurological functional outcome (mRS 0-2). Tumor occurrence and weight loss were associated with poor long-term functional outcomes in anti-LGI1 encephalitis, whereas in anti-Caspr2 encephalitis, predictors included behavioral disorder at acute phase, abnormalities in brain magnetic resonance imaging, higher modified Rankin scale scores at onset, poor response to the initial immunotherapy at 4 weeks, age at onset<30 years, and relapse ( p<0.05). Overall, 13.6% of anti-LGI1 encephalitis patients and 20% of anti-Caspr2 encephalitis patients had at least one relapse. Sleep disorder at the acute phase was the risk factor of relapse in anti-LGI1 encephalitis, while female, age at onset <30 years, and behavioral disorder at acute phase were the risk factors of relapse in anti-Caspr2 encephalitis (log rank p<0.05). Conclusion: The clinical characteristics such as age, gender, and tumor occurrence rates of anti-LGI1 encephalitis and anti-Caspr2 encephalitis in western China are different from those in the Western countries. Most patients in our study had favorable long-term functional outcomes. The relapse rates are still high in both types of encephalitis, which warrants caution.

Relapses of Anti-NMDAR, Anti-GABABR and Anti-LGI1 Encephalitis: A Retrospective Cohort Study

“…Similarly, a brainstem lesion on MRI was also reported to be associated with a greater chance of relapse ( 7 ). However, this association was not supported by our data and other literature ( 4 , 8 , 11 ). It may be due to the difference in patient characteristics and sample size across studies.…”

“…Immunotherapy delay was identified at a significance level of p < 0.05 ( Table 1 ). According to prior literature, gender ( 9 ), sleep disorders ( 11 ), tumor ( 15 ), abnormal brain MRI ( 7 ) and second-line immunotherapy ( 4 ) may be related to clinical relapse. Accordingly, these variables were retained for the multivariable cox regression model, despite p values > 0.05.…”

“…8 - 36.4% of patients with anti-NMDAR encephalitis may relapse ( 7 , 9 ). And relapses occurred in about 14 - 35% of anti-LGI1 encephalitis ( 10 , 11 ). The relapse rates varied across studies, indicating that AE is heterogeneous among people of different races.…”

“…Regarding the predictors of relapse, a recent cohort study from Western China suggested that female sex and delayed immunotherapy were relapse-related risk factors in anti-NMDAR encephalitis ( 9 ). Sleep disorders at the acute phase may increase the risk of relapse in anti - LGI1 encephalitis ( 11 ). The use of immunotherapy in the initial episode was related with a lower likelihood of relapses in anti-NMDAR encephalitis, and a relapse-decreasing effect of second-line immunotherapy was also reported ( 4 ).…”

Case Report: Paroxysmal hyperhidrosis as an initial symptom in a patient with anti-LGI1 encephalitis

“…Additionally, one third of the LGI1-IgG-seropositive patients had pain with or without sweating abnormality (5). Previous LGI1 encephalitis cases also described hyperhidrosis in 13.6% of patients and attributed it to autonomic dysfunction but without many details (23). Because no positive sign was found during examination of the autonomic nervous system (such as piloerection, tachypnea, or tachycardia), the unilateral hyperhidrosis with paroxysmal and repetitive features was interpreted as possible epilepsy.…”