NMDAR encephalitis presenting as akinesia in a patient with Parkinson disease

Advances in Potential Cerebrospinal Fluid Biomarkers for Autoimmune Encephalitis: A Review

Autoimmune encephalitis (AE) is a severe inflammatory disease of the brain. Patients with AE demonstrate amnesia, seizures, and psychosis. Recent studies have identified numerous associated autoantibodies (e.g., against NMDA receptors (NMDARs), LGI1, etc.) involved in the pathogenesis of AE, and the levels of diagnosis and treatment are thus improved dramatically. However, there are drawbacks of clinical diagnosis and treatment based solely on antibody levels, and thus the application of additional biomarkers is urgently needed. Considering the important role of immune mechanisms in AE development, we summarize the relevant research progress in identifying cerebrospinal fluid (CSF) biomarkers with a focus on cytokines/chemokines, demyelination, and nerve damage.

Diagnostic approach and treatment regimens in adult patients suffering from antibody-mediated or paraneoplastic encephalitis

Identification of patients with antibody-mediated encephalitis poses a diagnostic challenge and any delay in that respect will increase the interval until initiation of immunotherapy and may negatively affect the patient´s clinical outcome. Within this review we focus on therapeutic strategies in antibody-mediated encephalitis and propose how to proceed with patients, who are suspected to have encephalitis of unknown origin. We further briefly outline differences in treatment of paraneoplastic and antibody-mediated encephalitis according to its pathomechanisms.

Anti-NMDA receptor encephalitis in older adults: A systematic review of case reports

OBJECTIVE

To ascertain the clinical characteristics of anti-NMDA receptor encephalitis (NMDARE) in older patients.

METHOD

A systematic literature review using PubMed and Scopus of all published case reports of NMDARE was undertaken, from database inception to June 2020. From this, cases reporting on patients older than 65 years of age and whose diagnosis was confirmed by the presence of anti-NMDAR antibodies in CSF were selected.

RESULTS

23 case reports fulfilling the study's criteria were found. Median age was 70.1 years (range 65-84), fourteen were female (60.9%), and mostly presented with acute behavioral and cognitive changes (95.7%). Atypical psychosis occurred in eleven patients (47.8%) with a sudden onset and fluctuating clinical pattern of delusions (39.1%), hallucinations (30.4%), and motility disturbances (34.8%) including catatonia (17.4%). Nine patients presented with seizures (39.1%). Pleocytosis in CSF (>5 WBC) was described in twelve cases (52.2%). Eleven cases (47.8%) had abnormal brain magnetic resonance imaging (MRI) scans with limbic inflammatory lesions. Thirteen patients had an abnormal EEG (56.5%).

CONCLUSION

NMDARE should be included in the differential diagnosis of older patients who present with new psychiatric episodes, especially when characterized by sudden onset psychotic polymorphic symptomatology, fluctuating course with marked cognitive decline, and with catatonic features.