Réponse immunitaire et hypofonction NMDA (une piste étiopathogénique dans la psychose)

La compréhension des mécanismes biologiques des pathologies psychotiques est partielle. Cependant les progrès de la neuro-immunologie nous permettent de proposer de nouvelles pistes étiopathogéniques compatibles avec l'hypothèse déjà proposée d'un hypofonctionnement du récepteur NMDA dans la schizophrénie. Premièrement, les mécanismes neuroinflammatoires peuvent interagir avec le métabolisme du tryptophane et provoquer un hypofonctionnement du récepteur NMDA par production d'acide kynurenique. Deuxièmement, l'encéphalite à anticorps anti-récepteur NMDA est une maladie auto-immune de découverte récente qui provoque un hypofonctionnement du récepteur NMDA, et dont certaines formes frustres pourraient s'exprimer uniquement par des symptômes psychotiques. Deux cas cliniques psychiatriques sont ensuite proposés pour lesquels la présence d'anticorps anti-récepteur NMDA a été mis en évidence dans le sérum. L'étude de ces cas à l'appui de notre revue de la littérature nous permet de rediscuter le diagnostic et la prise en charge de ces patients, et nous amène à considérer l 'immunopsychiatrie comme une discipline d'avenir.PARIS13-BU Serge Lebovici (930082101) / SudocSudocFranceF

Stimulation du nerf vague dans le traitement de la dépression

International audienceVagus nerve stimulation (VNS) is an old, yet new, option for treatment-resistant depression. Despite several clinical trials over the last 15 years showing a consistent benefit-risk balance of the technic, VNS still struggles to find its place in our therapeutic algorithms. This is especially true in France, where only a few surgeries have been performed nationwide, all in the last year. The reasons behind this lag are manifolds; (1) psychiatrists usually do not consider surgical treatments, even when they are minimally invasive and reversible, (2) early VNS trials stumbled on methodological difficulties that are common to all invasive neurostimulation technics, and initially failed to provide strong evidence for its efficacy, and (3) VNS requires multidisciplinary teams involving psychiatrists and neurosurgeons that did not exist then. Nevertheless, studies of the past twenty years support VNS as a treatment of depression endowed with a unique efficacy profile: a long runner best at maintaining remission in hard-to-stabilize depression, even in the context of ECT withdrawal, and irrespective of whether it is unipolar or bipolar. Thus, VNS potentially addresses the unmet medical needs of some of the most severe and chronic patients with depression. This review aims at introducing VNS as a treatment option for depression, summarizing available evidence for its efficacy and tolerance, and delineating patient profiles that might benefit the most of such treatment

Dramatic reduction of psychiatric emergency consultations during lockdown linked to COVID ‐19 in Paris and suburbs

International audienc

Dramatic reduction of psychiatric emergency consultations during lockdown linked to COVID-19 in Paris and suburbs

ABSTRACTAimsThe COVID-19 pandemic and associated lockdown may have psychiatric consequences and increase the number of psychiatric emergency consultations. This study aimed to compare the number and characteristics of emergency psychiatric consultations during the four first weeks of the lockdown in three psychiatric emergency services from Paris and its suburbs, and to compare them to the same period in 2019.MethodsThree psychiatric centers in Paris and its suburbs took part in the study. We compared the number of total psychiatric emergency consultations during the 4 first weeks of the lockdown in France to the corresponding 4 weeks in 2019. We also compared the number of consultations during these 4-week time periods in 2020 and 2019 across different diagnostic categories.ResultsIn the 4 first weeks of the lockdown in France, 553 emergency psychiatry consultations were carried out, compared to 1224 consultations during the corresponding period of 2019, representing a 54.8 % decrease. This decrease was evident across all psychiatric disorders, including anxiety (number of consultations in 2020 representing 36.1 % of 2019), mood (41.1 %), and psychotic disorders (57.3 %). The number of suicide attempts also decreased (number of suicide attempts in 2020 representing 42.6 % of 2019). In comparison to 2019, the proportion of total consultations for anxiety disorders also decreased (16.6 % vs. 20.8 %), whilst the proportion of total consultations increased for psychotic disorders (31.1 % vs. 24.1 %).ConclusionsThe total number of psychiatric emergency consultations during lockdown dramatically decreased. The psychological consequences of lockdown may be delayed, indicating that psychiatric services should be prepared for a secondary increase in emergency presentations.</jats:sec

Dynamic disorganization of synaptic NMDA receptors triggered by autoantibodies from psychotic patients

Autoantibodies are found in neuropsychiatric conditions but without clear cellular mechanism and disease relevance. This study shows higher prevalence of autoantibodies against NMDAR receptors in schizophrenia patients, and patient-associated antibody can alter synaptic receptor trafficking and plasticity