Dados do Trabalho

Título

Brazilian autoimmune encephalitis network (BrAIN) study: antibody profile, clinical characteristics from a national wide network

Resumo

Introduction: Autoimmune encephalitis (AIE) is a group of inflammatory diseases characterized by prominent neuropsychiatric symptoms associated with neuroglial. Most common AIE is anti-NMDAR encephalitis, followed by anti-lgI1 and anti-CASPR2. Data on clinical features from developing countries are lacking.
Objectives: To describe the clinical and epidemiological profile of AIE in the Brazilian population and to verify the sensibility of the criteria
Methods: Brazilian Autoimmune Encephalitis Network (BrAIN) is a prospective study on AIE involving 17 centers from all Brazilian regions, in partnership with the Medical University of Vienna. Inclusion criteria are possible AIE according to Graus and agreement with informed consent. Demographic data, clinical presentation, presence of neoplasia, and treatment were compiled by the attending physician using REDCap. CSF analysis, EEG and brain MRI were also recorded. CSF and serum samples were tested using TBA for intraneuronal and surface antigens, followed by CBA or immunoblot.
Results: We included 547 patients and tested 512 for ANeA, which 402 (78,5%) fulfilled the probable AIE criteria and 103 (25.6%) were confirmed as seropositive AIE. The following ANeA were found anti-NMDAR (n=53, 51%), anti-MOG (n=12,11.5%), anti-GAD (n=10, 9.6%), anti-LGI1(n=7, n=6.7%), anti-Caspr2 (n=4, 3.8%), anti-AMPAR (n=4, 3.8%), anti-GABA-BR (n=3, 2.9%), anti-glyR (n=3, 2.9%). In pediatric population, it was detected only two antibodies: 21 anti-NMDAR (75%) and 7 anti-MOG (25%). Sensitivity of clinical criteria for possible AIE was 94%, and Specificity was 26%; Negative predictive value was 95%. Predictable variables of AIE in pediatric population were decreased level of consciousness (p=0.042), chorea (p=0.008), and dystonia (p=0.018) and in adults, movement (p=0.016) and memory impairment (p=0.042).
Conclusion:
Frequency of antibodies in AIE vary among populations, and we found unexpected high rates of anti-glycine and anti-MOG. In our population sensitivitty for AIE clinical criteria is low (26%) with high negative predictive value. Clinical variables that could help better predict AIE in children were decreased level of consciousness, chorea and dystonia. Among adults, movement and memory.Future scores for better AIE prediction should consider specific clinical presentation.

Palavras Chave

Autoimmune encephalitis