Ranking psychological interventions for post-stroke depression: A systematic review and network meta-analysis.

Infective endocarditis (IE) is a life-threatening infection involving heart valves, prostheses, or devices, often with complications due to systemic spread. Cardiac surgery advances and new antibiotic regimens have improved clinicians’ ability to manage the disease, although mortality and morbidity remain high (). IE pathophysiology is a complex thrombo-inflammatory disorder in which vascular damage, bacteremia, and bacterial virulence factors drive the development of endocardial vegetations. Despite a broad range of presentation patterns and severity, the most common causative pathogens of IE belong to a rather limited set of Gram-positive bacteria, including spp., spp., and spp. (). These pathogens enter the circulation from sites where they normally reside (e.g., skin, mouth, gut) or may be inoculated into the subject’s bloodstream during an invasive medical procedure. The presence of a damaged structure is likely to provide a favorable environment for the adhesion of circulating bacteria, which is the critical event for vegetation formation (). The term “human microbiota” refers to the complex community of microorganisms, primarily bacteria but also archaebacteria, fungi, and viruses, which inhabit the human body, particularly the gut (). Depending on the body site, these microbial communities exhibit specific compositional characteristics closely related to the unique features of the habitat (and the selective pressures encountered) and contribute to human health in a variety of ways, modulating critical physiological, metabolic, and immunological functions both locally and systemically (). Changes in the human microbiota (i.e., dysbiosis) have been associated with multiple diseases, even at distant sites. These are often associated with increased mucosal permeability, allowing the translocation of microorganisms and/or their components and prompting systemic effects (). With regard to IE, only a few studies have investigated its correlation with members of the host microbiota, namely the oral and gut microbiota (). In particular, most of these studies have focused on , the major dental caries pathogen, which is a common causative agent of IE (, ). More recently, pilot studies using next-generation sequencing to profile the oral microbiota of IE patients, patients at risk of IE, and healthy controls have revealed distinct microbial signatures that may represent a risk factor for IE as well as other systemic diseases (, ). A possible causal relationship between gut microbiota and IE has been suggested by a Mendelian randomization study, which provided a list of protective and predisposing genera and potential underlying mechanisms (). Further research in this area is clearly needed.