Della Vecchia Alessandra, Marazziti Donatella
Section of Psychiatry, Department of Clinical and Experimental Medicine, University of Pisa, and.
Saint Camillus International University of Health and Medical Sciences - UniCamillus, Rome, Italy.
Clin Neuropsychiatry. 2022 Aug;19(4):248-263. doi: 10.36131/cnfioritieditore20220407.
Recently, there has been a resurgence of interest in the relationship between infections and psychopathology, given the increasing data on the neurotropism and neurological/psychiatric morbidity of the SARS-COV2 virus, responsible for the current worldwide pandemic. Although the majority of observations were those obtained in mood and schizophrenic disorders, a few data are also available on the presence of bacterial or viral infections in patients suffering from obsessive-compulsive disorder (OCD). Therefore, given the limited information, the present paper aimed at reviewing the most updated evidence of infections in neuropsychiatric disorders and their possible mechanisms of actions, with a narrow focus on microbes in OCD.
This paper is a narrative review. The databases of PubMed, Scopus, Embase, PsycINFO and Google Scholar were accessed to research and collect English language papers published between 1 January 1980 and 31 December 2021. The data on PANDAS/PANS and those observed during severe brain infections were excluded.
Several pathogens have been associated with an increased risk to develop a broad spectrum of neuropsychiatric conditions, such as schizophrenia, mood disorders, autism, attention-deficit/hyperactivity disorder, anorexia nervosa, and post-traumatic stress disorder. Some evidence supported a possible role of infections also in the pathophysiology of OCD. Infections from Herpes simplex virus 1, Borna disease virus, Group A-Beta Hemolytic Streptococcus, Borrelia spp., and Toxoplasma gondii were actually found in patients with OCD. Although different mechanisms have been hypothesized, all would converge to trigger functional/structural alterations of specific circuits or immune processes, with cascade dysfunctions of several other systems.
Based on the current evidence, a possible contribution of different types of microbes has been proposed for different neuropsychiatric disorders including OCD. However, the currently available literature is meager and heterogeneous in terms of sample characteristics and methods used. Therefore, further studies are needed to better understand the impact of infectious agents in neuropsychiatric disorders. Our opinion is that deeper insights in this field might contribute to a better definition of biological underpinnings of specific clinical pictures, as well as to promote psychiatric precision medicine, with treatments based on altered pathological pathways of single patients. This might be particularly relevant in OCD, a disorder with a high proportion of patients who are resistant or do not respond to conventional therapeutic strategies.
鉴于目前有关导致全球大流行的SARS-CoV-2病毒的嗜神经性以及神经/精神疾病发病率的资料日益增多，近期人们对感染与精神病理学之间的关系再度产生了兴趣。尽管大多数观察结果来自情绪障碍和精神分裂症，但也有一些关于强迫症（OCD）患者存在细菌或病毒感染的数据。因此，鉴于信息有限，本文旨在回顾神经精神疾病中感染的最新证据及其可能的作用机制，重点关注OCD中的微生物。
本文为叙述性综述。检索了PubMed、Scopus、Embase、PsycINFO和谷歌学术数据库，以查找和收集1980年1月1日至2021年12月31日期间发表的英文论文。排除了有关儿童自身免疫性神经精神障碍相关链球菌感染/伴有链球菌感染的儿童自身免疫性神经精神障碍（PANDAS/PANS）以及严重脑部感染期间观察到的数据。
几种病原体与患多种神经精神疾病的风险增加有关，如精神分裂症、情绪障碍、自闭症、注意力缺陷多动障碍、神经性厌食症和创伤后应激障碍。一些证据支持感染在OCD的病理生理学中也可能起作用。实际上在OCD患者中发现了单纯疱疹病毒1型、博尔纳病病毒、A组β溶血性链球菌、疏螺旋体属和弓形虫的感染。尽管已经提出了不同的机制，但所有机制都将趋向于触发特定回路或免疫过程的功能/结构改变，以及其他几个系统的级联功能障碍。
基于目前的证据，已提出不同类型的微生物可能对包括OCD在内的不同神经精神疾病有影响。然而，就样本特征和所用方法而言，目前可得的文献既稀少又不统一。因此，需要进一步研究以更好地理解感染因子在神经精神疾病中的影响。我们认为，对该领域更深入的了解可能有助于更好地界定特定临床表现的生物学基础，以及推动精神科精准医学的发展，即根据单个患者改变的病理途径进行治疗。这在OCD中可能尤为重要，因为该疾病中有很大比例的患者对传统治疗策略耐药或无反应。
