Examining the Features of Neuroleptic Malignant Syndrome in Anti-NMDA Receptor Encephalitis: A Case-Control Study.

BACKGROUND: Anti-N-methyl-D-aspartate receptor encephalitis (ANMDARE) is a neuroimmunological disorder that frequently improves with immunotherapy. Symptomatic treatment with antipsychotics is common in the early stages when psychiatric symptoms predominate, and their use has been associated with serious side effects including neuroleptic malignant syndrome (NMS). The observation of an adverse response to antipsychotics, raising the suspicion of NMS, has been included as a criterion for possible autoimmune psychosis. METHODS: This case-control study included patients who received antipsychotics before referral to the National Institute of Neurology and Neurosurgery of Mexico, where they were diagnosed as having definite ANMDARE, and patients with ANMDARE who did not receive antipsychotics before referral. The neurologic and systemic features that are used to measure an adverse response to antipsychotics, raising the suspicion of NMS, were measured in both groups, including akinesia, autonomic instability, generalized rigidity, elevated concentrations of creatine phosphokinase, and hyperthermia. A logistic regression analysis was used to determine the relationship between the previous use of antipsychotics and the occurrence of NMS-like reactions. RESULTS: A total sample of 112 patients with definite ANMDARE were included in the study. Fifty patients received antipsychotics before being referred to our institution. In this group, thirty-six patients (72%) were initially classified as having an adverse response, raising the suspicion of NMS, with the following features: akinesia (64%), autonomic instability (58%), generalized rigidity (52%), elevated concentrations of creatine phosphokinase (50%), and hyperthermia (14%). Six patients fulfilled the criteria for NMS (12%). The comparison with patients who did not receive antipsychotics before the clinical assessment did not show a significant difference between groups regarding the frequency of akinesia, autonomic instability, generalized rigidity, elevated concentrations of creatine phosphokinase, or hyperthermia. Among different antipsychotics, only haloperidol was significantly associated with generalized rigidity as compared to patients who did not receive antipsychotics. CONCLUSIONS: Our study supports previous observations about the high frequency of autonomic dysfunction, hyperthermia, tachycardia, rigidity, and elevated creatine phosphokinase levels in patients with anti-NMDAR encephalitis following the administration of antipsychotic medications. Nevertheless, our study does not suggest a causal link between atypical antipsychotics and the onset of these neurological symptoms, as they were equally frequent among the group of patients who did not receive antipsychotic treatment.

Suicidal Thoughts and Behaviors in Anti-NMDA Receptor Encephalitis: Psychopathological Features and Clinical Outcomes.

OBJECTIVE: A wide variety of neuropsychiatric symptoms are described during the acute phase of anti-N-methyl-d-aspartate receptor encephalitis (ANMDARE), including psychosis, mania, depression, and catatonia, but there are few reports on suicidal thought and behaviors in ANMDARE. To address this gap in the literature, the authors measured the presence of suicidal thoughts and behaviors among a large cohort of Mexican patients diagnosed with definite ANMDARE. METHODS: This observational and longitudinal study included patients with definite ANMDARE hospitalized at the National Institute of Neurology and Neurosurgery of Mexico between 2014 and 2021. Suicidal thoughts and behaviors were assessed before and after treatment by means of a clinical interview with relatives and a direct clinical assessment with each patient. Thoughts of engaging in suicide-related behavior and acts of suicidal and nonsuicidal self-directed violence before and during hospitalization were recorded. RESULTS: From a total sample of 120 patients who fulfilled the diagnostic criteria for definite ANMDARE, 15 patients (13%) had suicidal thoughts and behaviors during the acute phase of the disease. All 15 of these patients experienced psychosis and had suicidal ideation with intention. Three patients engaged in preparatory behaviors and seven carried out suicidal self-directed violence. Psychotic depression and impulsivity were more frequent among those patients with suicidal thoughts and behaviors than among those without any form of suicidality. Four patients engaged in self-directed violence during hospitalization. Remission was sustained in 14 of 15 patients, with suicidal ideation and self-directed violence persisting during follow-up in only one patient. CONCLUSIONS: Suicidal thoughts and behaviors are not uncommon during the acute phase of ANMDARE. On the basis of our sample, the persistence of these features after immunotherapy is rare but may be observed. A targeted assessment of suicidal risk should be strongly considered in this population.

Inpatient Delirium in Guillain-Barré Syndrome: Frequency and Clinical Characteristics in a Mexican Hospital.

Background Delirium has a prevalence of 14%-56% in hospitalized patients. Risk factors include advanced age, invasive mechanical ventilation (IMV), and prolonged intensive care unit stay. Neuropsychiatric symptoms have been reported to be related to autoimmune responses secondary to Guillain-Barré syndrome (GBS) with direct involvement of the central nervous system (CNS) or to delirium. There are few reports of the frequency of delirium in patients with Guillain-Barré syndrome (GBS). Objective To describe the frequency of and the characteristics associated with delirium in patients with GBS. Material and methods A single-center, cross-sectional study was conducted in patients with GBS diagnosis between 2015 and 2019. The diagnosis of delirium was made using the Diagnostic and Statistical Manual of Mental Disorders, 5th Edition (DSM-5) criteria. We compared patients with and without delirium. We performed both univariate and multivariate analyses to identify factors associated with delirium. Results A total of 154 patients with GBS were included, of which 20 (12.9%) fulfilled the DSM-5 criteria for delirium. The mean age was 48 ± 18.2 years, the median Medical Research Council (MRC) sum score was 29.3 ± 21.9 points, 65% had bulbar cranial nerve involvement, 80% presented autonomic dysfunction, 85% had ICU stay, and 90% had mechanical ventilation requirement. In the multivariate analysis, the following were the independent factors for the development of delirium: age ≥ 60 (odds ratio (OR): 5.7; 95% confidence interval (CI): 1.3-23.5), time from symptom onset to admission ≤ 3 days (OR: 4.3; 95% CI: 1.1-16.8), autonomic dysfunction (OR: 13.1; 95% CI: 3-56), and intensive care unit stay (OR: 9.5; 95% CI: 2.1-42.6). Conclusion Delirium is not frequent in patients with Guillain-Barré syndrome. Patients with advanced age, rapid motor progression, bulbar cranial nerve involvement, prolonged intensive care unit stay, and mechanical ventilation need are more likely to present delirium.

[Autoinmune psychosis]. / Psicosis autoinmune.

With the advent of the description of autoimmune encephalitis by different neuronal cell-surface antibodies (anti-NMDAr, among others) and that psychosis may be the only manifestation without neurological symptoms (epilepsy, movement disorders, autonomic dysfunction, altered state of consciousness) in 6.5 % of patients, the term "autoimmune psychosis" has become remarkably interesting among researchers. In 2020, an international consensus for the description and diagnostic approach of autoimmune psychosis was created. Through this consensus, by taking different criteria into account, the definition of autoimmune psychosis was proposed at different degrees of certainty (possible, probable, and defined). The purpose of these criteria is to underpin the autoimmune origin in patients who present psychosis with atypical characteristics, thus justifying the realization of laboratory studies and complementary clinical tests (lumbar puncture, electroencephalogram, and magnetic resonance imaging of the brain); in addition, these criteria are applied in patients with psychosis without neurological symptoms that do not fully meet the criteria of autoimmune encephalitis. As in autoimmune encephalitis, the early initiation of immunotherapy has a direct impact on the functional prognosis of patients, so an early initiation of treatment must be considered in clinical scenarios of probable or definite autoimmune psychosis.

Con el advenimiento de la descripción de las encefalitis autoinmunes por diferentes anticuerpos neuronales de superficie (anti-NMDAr, entre otros) y que la psicosis puede ser la única manifestación sin síntomas neurológicos (epilepsia, alteraciones del movimiento, disautonomías, alteración del despierto) en 6.5 % de los pacientes, el término psicosis autoinmune ha retomado gran interés entre los investigadores. En 2020 se creó un consenso internacional para la descripción del término "psicosis autoinmune" y su abordaje diagnóstico. A través de este consenso, considerando diferentes criterios, se propone la definición de psicosis autoinmune en diferentes grados de certeza (posible, probable y definida). La finalidad de estos criterios es sustentar el origen autoinmune en pacientes que presenta psicosis con características atípicas, justificando así la realización de estudios de laboratorio y gabinete complementarios (punción lumbar, electroencefalograma, imagen de resonancia magnética de encéfalo); además, estos criterios se aplican a pacientes con psicosis sin síntomas neurológicos que no cumplen completamente con los criterios de encefalitis autoinmune. El inicio temprano de la inmunoterapia impacta directamente en el pronóstico funcional de los pacientes; se debe considerar el inicio temprano de tratamiento en cuadros clínicos de psicosis autoinmune probable o definida.