Preoperative Exclusive Enteral Nutrition Is Associated With Reduced Skin and Soft Tissue and Intra-abdominal Infections in Patients With Crohn's Disease Undergoing Intestinal Surgery: Results from a Meta-Analysis.

BACKGROUND: Malnutrition is an independent risk factor for adverse postoperative outcomes and is common among patients with Crohn's disease (CD). The objective of this meta-analysis was to precisely quantify the association of preoperative exclusive enteral nutrition (EEN) and total parenteral nutrition (TPN) with surgical outcomes in patients undergoing intestinal surgery for CD. METHODS: PubMed, Embase, and Scopus were queried for comparative studies evaluating the impact of preoperative nutritional support on postoperative outcomes in patients undergoing surgery for CD. Random effects modeling was used to compute pooled estimates of risk difference. Heterogeneity was assessed using I2. RESULTS: Fourteen studies, all nonrandomized cohort studies, met inclusion criteria for studying EEN. After pooling data from 14 studies (874 EEN treated and 1044 control patients), the relative risk of intra-abdominal septic complications was decreased 2.1-fold in patients receiving preoperative EEN (relative risk 0.47, 95% confidence interval [CI], 0.35-0.63, I2 = 0.0%). After pooling data from 9 studies (638 EEN treated and 819 control patients), the risk of skin and soft tissue infection was decreased 1.6-fold (relative risk 0.63; 95% CI, 0.42-0.94, I2 = 42.7%). No significant differences were identified in duration of surgery, length of bowel resected, or operative blood loss. Among the 9 studies investigating TPN, no significant differences were identified in infectious outcomes. CONCLUSIONS: Preoperative nutritional optimization with EEN was associated with reduced risk of infectious complications in CD patients undergoing intestinal surgery. Preoperative nutritional support with EEN should be considered for optimizing outcomes in CD patients requiring bowel resection surgery.

Pooled data from this meta-analysis demonstrated significantly decreased rates of skin/soft tissue and intra-abdominal infections following intestinal surgery for Crohn's disease after preoperative treatment with exclusive enteral nutrition.

A Scoping Review of Nutritional Biomarkers Associated with Food Security.

Food insecurity affects more than 40 million individuals in the United States and is linked to negative health outcomes due, in part, to poor dietary quality. Despite the emergence of metabolomics as a modality to objectively characterize nutritional biomarkers, it is unclear whether food security is associated with any biomarkers of dietary quality. This scoping review aims to summarize studies that examined associations between nutritional biomarkers and food security, as well as studies that investigated metabolomic differences between people with and without food insecurity. PubMed, Embase, Scopus, and AGRICOLA were searched through August 2022 for studies describing food insecurity and metabolic markers in blood, urine, plasma, hair, or nails. The 78 studies included consisted of targeted assays quantifying lipids, dietary nutrients, heavy metals, and environmental xenobiotics as biochemical features associated with food insecurity. Among those biomarkers which were quantified in at least five studies, none showed a consistent association with food insecurity. Although three biomarkers of dietary quality have been assessed between food-insecure versus food-secure populations, no studies have utilized untargeted metabolomics to characterize patterns of small molecules that distinguish between these two populations. Further studies are needed to characterize the dietary quality profiles of individuals with and without food insecurity.

Molecular Dialogues between Early Divergent Fungi and Bacteria in an Antagonism versus a Mutualism.

Fungal-bacterial symbioses range from antagonisms to mutualisms and remain one of the least understood interdomain interactions despite their ubiquity as well as ecological and medical importance. To build a predictive conceptual framework for understanding interactions between fungi and bacteria in different types of symbioses, we surveyed fungal and bacterial transcriptional responses in the mutualism between Rhizopus microsporus (Rm) (ATCC 52813, host) and its Mycetohabitans (formerly Burkholderia) endobacteria versus the antagonism between a nonhost Rm (ATCC 11559) and Mycetohabitans isolated from the host, at two time points, before and after partner physical contact. We found that bacteria and fungi sensed each other before contact and altered gene expression patterns accordingly. Mycetohabitans did not discriminate between the host and nonhost and engaged a common set of genes encoding known as well as novel symbiosis factors. In contrast, responses of the host versus nonhost to endobacteria were dramatically different, converging on the altered expression of genes involved in cell wall biosynthesis and reactive oxygen species (ROS) metabolism. On the basis of the observed patterns, we formulated a set of hypotheses describing fungal-bacterial interactions and tested some of them. By conducting ROS measurements, we confirmed that nonhost fungi increased production of ROS in response to endobacteria, whereas host fungi quenched their ROS output, suggesting that ROS metabolism contributes to the nonhost resistance to bacterial infection and the host ability to form a mutualism. Overall, our study offers a testable framework of predictions describing interactions of early divergent Mucoromycotina fungi with bacteria.IMPORTANCE Animals and plants interact with microbes by engaging specific surveillance systems, regulatory networks, and response modules that allow for accommodation of mutualists and defense against antagonists. Antimicrobial defense responses are mediated in both animals and plants by innate immunity systems that owe their functional similarities to convergent evolution. Like animals and plants, fungi interact with bacteria. However, the principles governing these relations are only now being discovered. In a study system of host and nonhost fungi interacting with a bacterium isolated from the host, we found that bacteria used a common gene repertoire to engage both partners. In contrast, fungal responses to bacteria differed dramatically between the host and nonhost. These findings suggest that as in animals and plants, the genetic makeup of the fungus determines whether bacterial partners are perceived as mutualists or antagonists and what specific regulatory networks and response modules are initiated during each encounter.