Le trouble bipolaire est une maladie mentale chronique touchant environ 1 à 2 % de la population générale, caractérisée par la survenue d’épisodes maniaques seuls ou en alternances avec des épisodes dépressifs. Les mécanismes sous-jacents à l’apparition et à la progression de la maladie bipolaire restent encore mal élucidés. L’objectif de notre étude était d’explorer l’effet du traitement psychotrope sur les variations des protéines sériques et des auto-anticorps au cours d’un épisode maniaque d’un trouble bipolaire de type I. Cette étude a été menée de janvier 2017 à juin 2019, en collaboration entre le service de psychiatrie B du CHU Hédi Chaker et le service d’immunologie du CHU Habib Bourguiba, à Sfax, Tunisie. Elle a porté sur un échantillon de 45 patients bipolaires en rechute maniaque. Après traitement, il y a eu une augmentation statistiquement significative des taux plasmatiques moyens des IgG et IgA et une diminution du taux plasmatique moyen de la fraction C4 du complément. Aucune variation significative des auto-anticorps n’a été notée après traitement. Le taux plasmatique moyen des IgM était significativement plus bas sous valproate de sodium. Sous antipsychotique atypique, le taux plasmatique moyen de la fraction C3 était statistiquement plus bas alors que sous antipsychotique classique, il était statistiquement plus élevé. Les protéines sériques ont montré plus de sensibilité que les auto-anticorps à l’effet du traitement psychotrope au cours d’une rechute maniaque.

Bipolar disorder is a chronic and disabling mental illness affecting approximately 1–2% of the general population, characterized by the occurrence of manic episodes alone or alternating with depressive episodes. Bipolar disorder is associated with significant morbidity, mortality and personal suffering. The mechanisms underlying the onset and progression of bipolar disease are still poorly understood. Recently, immunological dysfunctions have been suggested in the pathogenesis of bipolar disorder, and many studies have focused on the interaction between bipolar disorder and immunity. Immunological changes have been widely studied during depressive episodes but less explored during manic episodes. The objective of our study was to explore changes in serum proteins and autoantibodies after treatment for a manic episode of bipolar I disorder. This study was carried out over a 30-month period from January 2017 to June 2019, in collaboration between the psychiatry department B of the Hédi Chaker CHU and the immunology department of the Habib Bourguiba CHU, in Sfax, Tunisia. It focused on a sample of 45 bipolar patients with manic relapse, naïve to psychotropic treatment, or discontinuing treatment for a period of at least three months and without a history of autoimmune disease. The study was conducted in two stages : on admission and after treatment. The mean plasma levels of IgG and complement C3 fraction were significantly higher in bipolar patients with relapsing mania. Studies of variation in immunoglobulins and complement fractions during relapses of bipolar disorder have all objected to variations in these serum proteins, but their results were inconsistent regarding the direction of variation and the fractions affected. After treatment, there was a statistically significant increase in the mean plasma levels of IgG and IgA and a decrease in the mean plasma level of the C4 fraction of complement. No significant variation in autoantibodies was noted after treatment. The mean plasma IgM level was significantly lower with sodium valproate. On atypical antipsychotic medication, the mean plasma level of fraction C3 was statistically lower, whereas on conventional antipsychotic medication it was statistically higher. This is in line with the data in the literature which support the immunomodulatory role of thymoregulators and antipsychotics. Serum proteins have been more sensitive than autoantibodies to the effect of psychotropic therapy during manic relapse.