Effect Of Antibiotic Use Research Articles

Effect of β-lactam antibiotics on the gut microbiota of term neonates

β-Lactam antibiotics are a class of antibiotics commonly used to treat bacterial infections. However, the effects of β-lactam antibiotics on term neonatal intestinal flora have not been fully elucidated. Hospitalized full-term newborns receiving β-lactam antibiotics formed the antibiotic group (n = 67), while those without antibiotic treatment comprised the non-antibiotic group (n = 47). A healthy group included healthy full-term newborns (n = 16). Stool samples were collected for 16 S rDNA sequencing to analyze gut microbiota variations. Further investigation was carried out within the β-lactam antibiotic group, exploring the effects of antibiotic use on the newborns’ gut microbiota in relation to the duration and type of antibiotic administration, delivery method, and feeding practices. The antibiotic group exhibited significant difference of microbial community composition compared to the other groups. Genera like Klebsiella, Enterococcus, Streptococcus, Alistipes, and Aeromonas were enriched, while Escherichia-Shigella, Clostridium sensu stricto 1, Bifidobacterium, and Parabacteroides were reduced. Klebsiella negatively correlated with Escherichia-Shigella, positively with Enterobacter, while Escherichia-Shigella negatively correlated with Enterococcus and Streptococcus. Regardless of neonatal age, β-lactam antibiotics induced an elevated abundance of Klebsiella and Enterococcus. The impact on gut microbiota varied with the duration and type of antibiotic (cefotaxime or ampicillin/sulbactam). Compared to vaginal delivery, cesarean delivery after β-lactam treatment heightened the abundance of Klebsiella, Enterobacteriaceae_Unclassified, Lactobacillales_Unclassified, and Pectobacterium. Feeding patterns minimally influenced β-lactam-induced alterations. In conclusion, β-lactam antibiotic treatment for neonatal pneumonia and sepsis markedly disrupted intestinal microbiota, favoring Klebsiella, Enterococcus, Streptococcus, Alistipes, and Aeromonas. The impact of β-lactam varied by duration, type, and delivery method, emphasizing heightened disruptions post-cesarean delivery.

The contribution of animal antibiotic use to antibiotic resistance in human infections: Panel evidence from Denmark

Antibiotic use (ABU) in animals is postulated to be a major contributor to selection of antibiotic resistance (ABR) which subsequently causes infections in human populations. However, there are few quantifications of the size of this association. Denmark, as a country with high levels of pig production and strong ABR surveillance data, is an ideal case study for exploring this association.This study compiles a dataset on ABU across several animal species and antibiotic classes, and data on the rate of antibiotic resistance (ABR) in humans across key pathogens, in Denmark over time (2010−2020). Panel data regressions (fixed effects, random effects, first difference and pooled ordinary least squares) were used to test the association between the level of ABR in human isolates and the level of ABU in animals.A positive relationship was identified between ABR in humans and ABU in cattle, with some evidence of a positive relationship for poultry and companion animals, and a negative relationship for fish, although the latter is likely driven by confounding factors. When lagging ABU by one year, the effect of ABU in cattle and companion animals remained similar, the effect of ABU in poultry fell in size, and ABU in fish was no longer significant, perhaps due to differences in life cycle length among animal species. Additional covariates were explored, including pet populations, agricultural production and GDP per capita (at purchasing power parity), but these results were limited by the statistical power of the dataset. Under all models, animal ABU determined only a minority of the change in human ABR levels in this context with adjusted R2 ranging from 0.19 to 0.44.This paper supports the role of animal ABU in determining human ABR levels but suggests that, despite comprising a large portion of systemwide ABU, it only explains a minority of the variation. This is likely driven in part by data limitations, and could also be due to a persistence of ABR once resistance has emerged, suggesting a significant role for socioeconomic and transmission factors in bringing ABR down to desirable levels.

Antibiotic use attenuates response to immune checkpoint blockade in urothelial carcinoma via inhibiting CD74-MIF/COPA: revealing cross-talk between anti-bacterial immunity and anti-tumor immunity through a tumor marker prognostic study.

Immune checkpoint blockade (ICB) has emerged as a promising therapy for both resectable urothelial carcinoma (UC) patients preparing for radical surgery and unresectable UC patients, whereas the objective response rate of ICB remains unsatisfactory due to various factors. Antibiotic (ATB) use can influence intra-tumoral bacteria, which may further reduce ICB efficacy. The study aims to evaluate the effects of ATB use on prognosis and response in UC patients undergoing ICB, and explore potential molecular mechanisms of ATBs and intra-tumoral bacteria impacting UC immune microenvironment. Pooled analyses, synthesizing evidence from 12 studies and 3496 UC patients with ICB treatment, was conducted via a meta-analysis. In addition, single-cell RNA and single-cell microbiome data were analyzed based on eight UC samples and 63185 single cells. Bulk RNA sequencing and clinical data from a single-arm, multi-center, atezolizumab-treated, phase 2 trial, IMvigor210, were used for validation. The study is registered at PROSPERO (XXX) and at Research Registry (XXX). ATB use exhibited worse overall survival (HR=1.46, 95%CI=[1.20, 1.77], P<0.001, heterogeneity I²=51%) and lower objective response (OR=0.43, 95%CI=[0.27, 0.68], P<0.001, heterogeneity I²=0%) in UC patients receiving ICB. Single-cell transcriptome and single-cell microbiome analyses identified the presence of intra-tumoral bacteria was obviously related to elevated anti-bacterial immune functions; and anti-bacterial immunity was positively correlated to anti-tumor immunity in UC immune microenvironment. Intra-tumoral bacteria could up-regulate CD74-MIF/COPA signaling of immune cells and activation of CD74-MIF/COPA mediated the promotion of T cell anti-tumor function induced by anti-bacterial immune cells. UC patients with higher CD74-MIF/COPA signaling carried better overall survival (HR=1.60, 95%CI=[1.19, 2.15], P=0.002) in IMvigor210 immunotherapy cohort. ATB use reduces overall survival and objective response to ICB in UC patients. Anti-bacterial immune cell functions induced by intra-cellular bacteria in UC microenvironment might up-regulate the function of anti-tumor T immune cells via activating CD74-MIF/COPA, whereas ATB could inhibit the above process through killing intra-cellular bacteria and result in poorer clinical benefit of ICB. The use of ATB should be considered carefully during neoadjuvant immunotherapy period for resectable UC patients preparing for radical surgery and during immunotherapy period for unresectable UC patients.

MIC distribution analysis identifies differences in AMR between population sub-groups.

Phenotypic data, such as the minimum inhibitory concentrations (MICs) of bacterial isolates from clinical samples, are widely available through routine surveillance. MIC distributions inform antibiotic dosing in clinical care by determining cutoffs to define isolates as susceptible or resistant. However, differences in MIC distributions between patient sub-populations could indicate strain variation and hence differences in transmission, infection, or selection. The Vivli AMR register contains a wealth of MIC and metadata for a vast range of bacteria-antibiotic combinations. Using a generalisable methodology followed by multivariate regression, we explored MIC distribution variations across 4 bacteria, covering 7,135,070 samples, by key population sub-groups such as age, sex and infection type, and over time. We found clear differences between MIC distributions across various patient sub-groups for a subset of bacteria-antibiotic pairings. For example, within Staphylococcus aureus, MIC distributions by age group and infection site displayed clear trends, especially for levofloxacin with higher resistance levels in older age groups (odds of 2.17 in those aged 85+ compared to 19-64), which appeared more often in men. This trend could reflect greater use of fluoroquinolones in adults than children but also reveals an increasing MIC level with age, suggesting either transmission differences or accumulation of resistance effects. We also observed high variations by WHO region, and over time, with the latter likely linked to changes in surveillance. We found that MIC distributions can be used to identify differences in AMR levels between population sub-groups. Our methodology could be used more widely to unveil hidden transmission sources and effects of antibiotic use in different patient sub-groups, highlighting opportunities to improve stewardship programmes and interventions, particularly at local scales.

Body composition and metabolic consequences of antibiotics most frequently administered to newborns in intensive care units: an experimental study in healthy newborn rats.

The increasing overuse of antibiotics in recent years has led to antibiotics being the most prescribed drugs for pediatric patients, and 72% of patients in the neonatal intensive care unit are treated with antibiotics. One effect of antibiotic use is the alteration of the microbiota, which is associated with metabolic disorders, including obesity. This experimental study in newborn rats compared the administration of ampicillin/meropenem (Access/Watch groups) at 100/10 μg/g every 12 h, cefotaxime 200 μg/g every 24 h (Watch group), and amikacin 15 μg/g every 24 h (Access group) versus saline solution as the control. Each antibiotic was adjusted to the required dosages based on weight, and the doses were administered intraperitoneally daily for 5 days to 10-14 newborn male rats per group. A comparison of the morphometric and biochemical parameters registered on day 28 was performed using ANOVA. Amikacin had the largest effect on morphometric measurements, and low-density lipoprotein cholesterol, while cefotaxime had the largest effect on glucose and triglycerides, whereas ampicillin/meropenem produced the weakest effect on the measured parameters. The administration of antibiotics in the neonatal stage can affect the body composition of rats as well as the lipid and carbohydrate serum levels. Future studies should evaluate the toxicity of antibiotics in immature neonatal organs and could help to improve therapeutic decisions and prevent the unjustified use of antibiotics in newborns, thereby reducing metabolic consequences.

Antibiotics influence the risk of anti-drug antibody formation during anti-TNF therapy in Chinese inflammatory bowel disease patients.

Aims: The formation of anti-drug antibodies (ADAs) during anti-tumor necrosis factor (anti-TNF) therapy is reported to lead to reducing serum drug levels, which may bring about a loss of response to treatment. Previous research has suggested an association between specific antibiotic classes and ADA formation during anti-TNF therapy. However, there are few studies specifically examining this association in Chinese inflammatory bowel disease (IBD) patients. Therefore, our study aimed to evaluate the possible effect of antibiotic use on ADA formation to anti-TNF therapy in Chinese patients with IBD. Methods: A total of 166 patients with IBD, including 149 with Crohn's disease (CD) and 17 with ulcerative colitis (UC), were included in this retrospective analysis. These patients were initially treated with anti-TNF therapy (infliximab or adalimumab) after January 2018 and reviewed with available ADA levels before October 2023. After univariable analysis of all the variables, a multivariate Cox proportional hazards model was used to assess the association between antibiotic use and ADA development. Results: Among 166 IBD patients treated with infliximab (108/166, 65.1%) or adalimumab (58/166, 34.9%), 31 patients (18.7%) were measured as positive ADA levels. Cox proportional hazard model demonstrated an increased risk of ADA formation in IBD patients who used β-lactam-β-lactamase inhibitor combinations (BL-BLIs) (HR = 5.143, 95%CI 1.136-23.270, p = 0.033), or nitroimidazoles (HR = 4.635, 95%CI 1.641-13.089, p = 0.004) during 12months before the ADA test. On the contrary, a reduced risk was noted in patients treated with fluoroquinolones (HR = 0.258, 95% CI 0.072-0.924, p = 0.037). Moreover, the median serum infliximab or adalimumab concentration in patients with positive ADA levels was significantly lower than that in patients with negative ADA levels (infliximab: 0.30 vs. 1.85μg/mL, p < 0.0001; adalimumab: 0.45 vs. 7.55μg/mL, p = 0.0121). Conclusion: ADA development is associated with various antibiotic classes. BL-BLIs and nitroimidazoles might increase the risk of ADA formation during anti-TNF therapy in Chinese IBD patients, while the treatment with fluoroquinolones could probably reduce such risk. There were certain limitations in the retrospective analysis of the study, therefore, the results are just for reference, and other studies are needed to further confirm our findings.

The individual response to antibiotics and diet - insights into gut microbial resilience and host metabolism.

Antibiotic use disrupts microbial composition and activity in humans, but whether this disruption in turn affects host metabolic health is unclear. Cohort studies show associations between antibiotic use and an increased risk of developing obesity and type 2 diabetes mellitus. Here, we review available clinical trials and show the disruptive effect of antibiotic use on the gut microbiome in humans, as well as its impact on bile acid metabolism and microbial metabolites such as short-chain fatty acids. Placebo-controlled human studies do not show a consistent effect of antibiotic use on body weight and insulin sensitivity at a population level, but rather an individual-specific or subgroup-specific response. This response to antibiotic use is affected by the resistance and resilience of the gut microbiome, factors that determine the extent of disruption and the speed of recovery afterwards. Nutritional strategies to improve the composition and functionality of the gut microbiome, as well as its recovery after antibiotic use (for instance, with prebiotics), require a personalized approach to increase their efficacy. Improved insights into key factors that influence the individual-specific response to antibiotics and dietary intervention may lead to better efficacy in reversing or preventing antibiotic-induced microbial dysbiosis as well as strategies for preventing cardiometabolic diseases.

Early life exposure of infants to benzylpenicillin and gentamicin is associated with a persistent amplification of the gut resistome

BackgroundInfant gut microbiota is highly malleable, but the long-term longitudinal impact of antibiotic exposure in early life, together with the mode of delivery on infant gut microbiota and resistome, is not extensively studied.MethodsTwo hundred and eight samples from 45 infants collected from birth until 2 years of age over five time points (week 1, 4, 8, 24, year 2) were analysed. Based on shotgun metagenomics, the gut microbial composition and resistome profile were compared in the early life of infants divided into three groups: vaginal delivery/no-antibiotic in the first 4 days of life, C-section/no-antibiotic in the first 4 days of life, and C-section/antibiotic exposed in first 4 days of life. Gentamycin and benzylpenicillin were the most commonly administered antibiotics during this cohort’s first week of life.ResultsNewborn gut microbial composition differed in all three groups, with higher diversity and stable composition seen at 2 years of age, compared to week 1. An increase in microbial diversity from week 1 to week 4 only in the C-section/antibiotic-exposed group reflects the effect of antibiotic use in the first 4 days of life, with a gradual increase thereafter. Overall, a relative abundance of Actinobacteria and Bacteroides was significantly higher in vaginal delivery/no-antibiotic while Proteobacteria was higher in C-section/antibiotic-exposed infants. Strains from species belonging to Bifidobacterium and Bacteroidetes were generally persistent colonisers, with Bifidobacterium breve and Bifidobacterium bifidum species being the major persistent colonisers in all three groups. Bacteroides persistence was dominant in the vaginal delivery/no-antibiotic group, with species Bacteroides ovatus and Phocaeicola vulgatus found to be persistent colonisers in the no-antibiotic groups. Most strains carrying antibiotic-resistance genes belonged to phyla Proteobacteria and Firmicutes, with the C-section/antibiotic-exposed group presenting a higher frequency of antibiotic-resistance genes (ARGs).ConclusionThese data show that antibiotic exposure has an immediate and persistent effect on the gut microbiome in early life. As such, the two antibiotics used in the study selected for strains (mainly Proteobacteria) which were multiple drug-resistant (MDR), presumably a reflection of their evolutionary lineage of historical exposures—leading to what can be an extensive and diverse resistome.31ajk8a-14RKZLdCXmKHuwVideo

Effectiveness evaluation of antibiotic use in patients with Methicillin-resistant Staphylococcus aureus (MRSA) infection: a review

Methicillin-resistant Staphylococcus aureus (MRSA) is a pathogen that become a public health problem due to its ability to be resistant to more than three classes of antibiotics. Evaluation of the effectiveness of antibiotic use in patients with MRSA is important to optimize antibiotic use and to control antibiotic resistance. This article review attempted to evaluate the effectiveness of antibiotics in patients with MRSA. This review explored the results of previous research from PubMed as a literature source and the PRISMA flow diagram as a protocol for the article selection process. Eight studies reviewed the evaluation of the effectiveness of antibiotic use in MRSA patients with various clinical conditions, such as uncomplicated wound infections, cellulitis and no wound, purulent drainage or abscess, cSSSI infections caused by MRSA, infections caused by MRSA bacteremia and nosocomial infections caused by MRSA. In conclusion, the effectiveness of antibiotics in patients with MRSA infection depends on the clinical condition of each patient. Therefore, the use of antibiotics is adjusted based on the type of infection and the efficacy of the antibiotics. Combination therapy is recommended for MRSA patients considering its life-threatening ability.

Bacteriocin-Producing Probiotic Lactic Acid Bacteria against Hospital Strains of Staphylococcus aureus and Escherichia coli

It is now accepted that the human microbiome plays a key role in human health, and disturbances in the microbiome can cause or aggravate a range of diseases, from metabolic to immune disorders and mood disorders [1]. In addition, microbiota imbalance or dysbiosis may arise due to careless use of antibiotics in humans and animals, leading to the emergence of antibiotic-resistant bacteria that may compromise the effectiveness of antibiotics, so there is an urgent need to identify and develop new strategies to combat antibiotics resistance [2,3]. So far, probiotics are considered as perspective alternatives to antibiotics [4]. Probiotics are defined by the FAO/WHO as “Live microorganisms which when administered in adequate amounts confer a health benefit on the host” and they are successfully used for preservation of the microbial community [5].Moreover, bacteriocin-producing commensal microbes have the capacity to eliminate specific colonizing pathogens from various human body sites, and, as many bacteriocins have only narrow activity ranges they can be used for precision therapy and infections prevention [6]. Lactic acid bacteria, particularly lactobacilli, are the best known probiotics that modulate the immune system, and produce significant amounts of bioactive compounds, including bacteriocins, to eliminate pathogens and limit the clinical effects of antibiotic use [7, 8].

Adverse Effect of the Duration of Antibiotic Use Prior to Immune Checkpoint Inhibitors on the Overall Survival of Patients with Recurrent Gynecologic Malignancies.

Antibiotic use preceding immune checkpoint inhibitor (ICI) treatment has been associated with a decreased efficacy of ICI in solid tumors. In this study, we evaluated the effect of antibiotic use before ICI therapy on oncological outcomes. We examined patients with recurrent gynecologic malignancies at two academic institutions. The clinical data, including antibiotic use within 60 days of ICI initiation, type of antibiotics, reasons for antibiotic use, body mass index, tumor site, chemotherapy-free interval, prior history of radiotherapy, disease control rate (DCR), and overall survival (OS), were assessed. Of 215 patients, 22.9% (n = 47) received antibiotics before ICI treatment. The most common cancer was ovarian (52.1%, n = 112), followed by cervical (24.7%, n = 53) and endometrial (16.7%, n = 36). When we divided the cohort based on antibiotic use before ICIs, there were no significant differences in the DCR and baseline characteristics between the two groups. On multivariate analyses, the variables associated with poor OS were previous use of antibiotics for a cumulative duration of >14 days (HR 2.286, 95% CI 1.210-4.318; p = 0.011); Eastern Cooperative Oncology Group 2 or 3 (HR 4.677, 95% CI 2.497-8.762; p < 0.001); and chemotherapy-free interval of <6 months (HR 2.007, 95% CI 1.055-3.819; p = 0.034). Prior use of antibiotics for a cumulative duration of >14 days was associated with reduced survival in recurrent gynecologic malignancies.

Antibiotic treatment and survival in non-small cell lung cancer patients receiving immunotherapy: a systematic review and meta-analysis.

In patients with non-small cell lung cancer (NSCLC), immune checkpoint inhibitors (ICIs) are an effective mode of treatment. Despite their efficacy, responses to ICIs have been shown to differ based on several factors; for example, antibiotic use prior to and/or during immunotherapy has been associated with lower survival in NSCLC patients. The objective of this study is to provide an updated review of the literature and to fill in important knowledge gaps by accounting for potential confounding in the relationship between ICIs and survival. We performed a systematic review and meta-analysis on peer-reviewed studies that examined the effects of antibiotic use on overall survival (OS) and progression-free survival (PFS) in NSCLC patients treated with ICIs. We searched MEDLINE for studies published up to June 30th, 2023 that included NSCLC patients treated with anti-programmed cell death protein 1 (PD-1) or programmed death-ligand 1 (PD-L1) agents, who received antibiotics before and/or during immunotherapy, and included a control group who did not receive antibiotics and had available data on the associations between antibiotics and OS and PFS. We calculated aggregated crude OS and PFS for all studies, and only for studies that reported multivariable hazard ratios (HRs). Risk of bias was assessed using a funnel plot. All results were synthesized and displayed using the metaphor statistical package in R, version 4.2.1. Nineteen studies, conducted between 2017 and 2022, met the inclusion criteria, and included 2,932 patients with advanced and/or metastatic NSCLC. Compared to those who did not receive antibiotics, immunotherapy patients who did had a significantly reduced PFS (HR: 1.22, 95% CI: 1.03-1.44) and OS (HR: 1.56, 95% CI: 1.23-1.99). Adjusted HRs were even more pronounced (OS HRadj: 1.67, 95% CI: 1.23-2.27, PFS HRadj: 1.64, 95% CI: 1.16-2.32). NSCLC patients treated with antibiotics have significantly lowered survival compared with patients not treated with antibiotics. These results support the hypothesis that antibiotic use in conjunction with ICI among NSCLC patients lowers survival. Limitations of this analysis include the use of studies available only on a single database, limiting the literature search to NSCLC patients, which may impact the generalizability of results to other cancer patient populations, and the inability to account for and adjust the estimates for the same variables (e.g., age, sex) across all studies. Nevertheless, our findings underscore the importance of taking antibiotic use into consideration when using ICIs to treat NSCLC and suggest that confounders should be taken into account when designing future similar studies.

The Impact of Antibiotic Use on Animal Surgery and Animal Feed: A Review of the Relevant Literature

The administration of antibiotics in animal surgery and animal feed is a widely accepted practice intended to mitigate infection risks. Using antibiotics in animals is one of the most effective treatments available. However, when antibiotics are used imprudently can lead to severe consequences for animal health and may affect the ecosystem in many ways. This literature review aims to assess the effects of antibiotic use in animal surgery and animal feeding. The review explores the associated risks and benefits. This review aims to present an overview of the impact of antibiotics on animals in both surgical and feeding ways. Including the advantages and disadvantages that affect animals and the environment. To benefit those who are interested in veterinary or antibiotics administration Keywords: Antibiotics, Animal surgery, Animal feed, Animal Health, Veterinary medicine, Livestock

Characteristics of Exacerbation and Antibiotic Usage in Treatment for Exacerbation of COPD Patients in National Lung Hospital (2022-2023)

Abstract: Exacerbations of COPD are important events in the progression of the disease, being the leading cause of hospitalization and mortality. Bacterial respiratory infections are one of the main causes of exacerbations. This retrospective study was described characteristics of exacerbation and antibiotic use in COPD exacerbation patients hospitalized at the National Lung Hospital. This study included 200 hospitalized patients from January2022 to June 2023. Many patients in the study sample were male (90%), 76% of patients had two or more exacerbations per year. The most isolated bacteria are Haemophilus influenzae, Pseudomonas aeruginosa, Acinetobacter baumannii. There were 77,5% pneumonia patients had Drug Susceptibility Tests (DST), and 54,7% of patients had antibiotic regimens consistent with the DST. The results of this study provide a reliable basis for selecting and improving the effectiveness of antibiotic use in the treatment of COPD exacerbations, improving outcomes and survival prognosis for patients.&#x0D; Keywords: COPD, exacerbation, bacteria, antibiotics.

Antimicrobial Activity of Basil (Ocimum basilicum L.) Against Gram-Negative Bacteria Involved in Pneumonia Infection

Infectious diseases are still a global problem, for example, acute respiratory infections (SARI). Resistance in pneumonia involving Gram-negative bacterial infection reduces the effectiveness of antibiotic use and increases the length of hospital stay. This study examines the potential of antimicrobial compounds from basil plants against isolates of Gram-negative bacteria involved in pneumonia infection. This research is an experimental study through several stages: basil extraction, initial screening of bioactive compounds, isolation and identification of bacteria from sputum, and testing for antimicrobial activity of basil extracts. Sputum samples were collected from 43 pneumonia patients (male and female) involving Klebsiella pneumoniae, Acinetobacter baumannii, Enterobacter aerogenes, Pseudomonas aeruginosa, Serratia marcescens, Proteus mirabilis, and Escherichia coli. The inhibitory activity against pathogenic bacteria was directly proportional to the basil extract concentration. Initial screening for phytochemical compounds showed that the extracts of basil leaves and stems contained active compounds of tannins and flavonoids. The 25% concentration of basil extract was the minimum inhibitory concentration (MIC) against the test bacteria. The 100% basil extract concentration produced the largest inhibition zone i.e., 10.93 mm. The overall findings of this study provide baseline information for the possible use of the Ocimum basilicum extract in the treatment of pneumonia involving Gram-negative bacteria.

Fiber supplementation protects from antibiotic-induced gut microbiome dysbiosis by modulating gut redox potential

Antibiotic-induced gut dysbiosis (AID) is a frequent and serious side effect of antibiotic use and mitigating this dysbiosis is a critical therapeutic target. We propose that the host diet can modulate the chemical environment of the gut resulting in changes to the structure and function of the microbiome during antibiotic treatment. Gut dysbiosis is typically characterized by increases in aerobic respiratory bacterial metabolism, redox potential, and abundance of Proteobacteria. In this study, we explore dietary fiber supplements as potential modulators of the chemical environment in the gut to reduce this pattern of dysbiosis. Using defined-diets and whole-genome sequencing of female murine microbiomes during diet modulation and antibiotic treatment, we find that fiber prebiotics significantly reduced the impact of antibiotic treatment on microbiome composition and function. We observe reduced abundance of aerobic bacteria as well as metabolic pathways associated with oxidative metabolism. These metatranscriptomic results are corroborated by chemical measurements of eH and pH suggesting that fiber dampens the dysbiotic effects of antibiotics. This work indicates that fiber may act as a potential therapeutic for AID by modulating bacterial metabolism in the gut to prevent an increase in redox potential and protect commensal microbes during antibiotic treatment.

The effects of antibiotic use on the dynamics of the microbiome and resistome in pigs

Antibiotics are widely used in pig farming across the world which has led to concerns about the potential impact on human health through the selection of antibiotic resistant pathogenic bacteria. This worry has resulted in the development of a production scheme known as pigs Raised Without Antibiotics (RWA), in which pigs are produced in commercial farms, but are ear-tagged as RWA until slaughter unless they receive treatment, thus allowing the farmer to sell the pigs either as premium priced RWA or as conventional meat. Development of antibiotic resistance in pig farming has been studied in national surveys of antibiotic usage and resistance, as well as in experimental studies of groups of pigs, but not in individual pigs followed longitudinally in a commercial pig farm. In this study, a cohort of RWA designated pigs were sampled at 10 time points from birth until slaughter along with pen-mates treated with antibiotics at the same farm. From these samples, the microbiome, determined using 16S sequencing, and the resistome, as determined using qPCR for 82 resistance genes, was investigated, allowing us to examine the difference between RWA pigs and antibiotic treated pigs. We furthermore included 176 additional pigs from six different RWA farms which were sampled at the slaughterhouse as an endpoint to substantiate the cohort as well as for evaluation of intra-farm variability. The results showed a clear effect of age in both the microbiome and resistome composition from early life up until slaughter. As a function of antibiotic treatment, however, we observed a small but significant divergence between treated and untreated animals in their microbiome composition immediately following treatment, which disappeared before 8 weeks of age. The effect on the resistome was evident and an effect of treatment could still be detected at week 8. In animals sampled at the slaughterhouse, we observed no difference in the microbiome or the resistome as a result of treatment status but did see a strong effect of farm origin. Network analysis of co-occurrence of microbiome and resistome data suggested that some resistance genes may be transferred through mobile genetic elements, so we used Hi-C metagenomics on a subset of samples to investigate this. We conclude that antibiotic treatment has a differential effect on the microbiome vs. the resistome and that although resistance gene load is increased by antibiotic treatment load, this effect disappears before slaughter. More studies are needed to elucidate the optimal way to rear pigs without antibiotics.

Antibiotics use patterns in end-of-life cancer patients and medical staff's perception of antimicrobial stewardship programs.

While most cancer patients with end-of-life (EOL) care receive antibiotic treatments, antibiotic use should be decided appropriately considering the benefits, side effects, resistance, and cost effects. Antimicrobial stewardship programs (ASP) are important for patients with EOL care, but there is limited study analyzing actual antibiotic use in EOL care and the perceptions of Korean medical staff. Electronic medical records of 149 deceased cancer patients hospitalized in the medical hospitalist units at Asan Medical Center in Seoul from May 2019 to September 2021 were reviewed. Basic information, antibiotic use, duration, and changes were investigated. We surveyed medical staff's perceptions of antibiotics in cancer patients with EOL. Of the 149 cancer patients with EOL care, 146 (98.0%) agreed with physician orders for life-sustaining treatment (POLST). In total, 143 (95.9%) received antibiotics, 110 (76.9%) received combination antibiotic treatment, and 116 (81.1%) were given antibiotics until the day of death. In a survey of 60 medical staff, 42 (70.0%) did not know about ASP, and 24 (40.0%) thought ASP was important in EOL care. Nineteen doctors (31.7%) discussed the use or discontinuation of antibiotics with patients or caregivers when writing POLST, but only 8 patients (5.6%) stopped antibiotics after POLST. Most cancer patients with EOL care continue to receive antibiotics until just before their death. A careful approach is needed, considering the benefits and side effects of antibiotic use, and the patient's right to self-decision. It is necessary to actively improve awareness of ASP and its importance for medical staff.

Utility of Diagnostic Markers in Late Periprosthetic Joint Infection Workup for Total Knee Arthroplasty Patients Who Received Antibiotics 48 Hours Before Aspiration

BackgroundDiagnosing periprosthetic joint infection (PJI) following total knee arthroplasty (TKA) remains challenging despite recent advancements in testing and evolving criteria over the last decade. Moreover, the effects of antibiotic use on diagnostic markers are not fully understood. Thus, this study sought to determine the influence of antibiotic use within 48 hours before knee aspiration on synovial and serum laboratory values for suspected late PJI. MethodsPatients who underwent a TKA and subsequent knee arthrocentesis for PJI workup at least 6 weeks after their index arthroplasty were reviewed across a single healthcare system from 2013 to 2020. Median synovial white blood cell (WBC) count, synovial polymorphonuclear (PMN) percentage, serum erythrocyte sedimentation rate (ESR), serum C-reactive protein (CRP), and serum WBC count were compared between immediate antibiotic and nonantibiotic PJI groups. Receiver operating characteristic (ROC) curves and Youden’s index were used to determine test performance and diagnostic cutoffs for the immediate antibiotics group. ResultsThe immediate antibiotics group had significantly more culture-negative PJIs than the no antibiotics group (38.1 versus 16.2%, P = .0124). Synovial WBC count demonstrated excellent discriminatory ability for late PJI in the immediate antibiotics group (area under curve, AUC = 0.97), followed by synovial PMN percentage (AUC = 0.88), serum CRP (AUC = 0.86), and serum ESR (AUC = 0.82). ConclusionAntibiotic use immediately preceding knee aspiration should not preclude the utility of synovial and serum lab values for the diagnosis of late PJI. Instead, these markers should be considered thoroughly during infection workup considering the high rate of culture-negative PJI in these patients. Level of EvidenceLevel III, retrospective comparative study.

ANTIBIOTIC PROPHYLAXIS FOR ABDOMINAL SURGERY: WHEN TO RECOMMEND? BRAZILIAN COLLEGE OF DIGESTIVE SURGERY POSITION PAPER.

Surgical antibiotic prophylaxis is an essential component of perioperative care. The use of prophylactic regimens of antibiotics is a well-established practice that is encouraged to be implemented in preoperative/perioperative protocols in order to prevent surgical site infections. The aim of this study was to emphasize the crucial aspects of antibiotic prophylaxis in abdominal surgery. Antibiotic prophylaxis is defined as the administration of antibiotics before contamination occurs, given with the intention of preventing infection by achieving tissue levels of antibiotics above the minimum inhibitory concentration at the time of surgical incision. It is indicated for clean operations with prosthetic materials or in cases where severe consequences may arise in the event of an infection. It is also suitable for all clean-contaminated and contaminated operations. The spectrum of action is determined by the pathogens present at the surgical site. Ideally, a single intravenous bolus dose should be administered within 60 min before the surgical incision. An additional dose should be given in case of hemorrhage or prolonged surgery, according to the half-life of the drug. Factors such as the patient's weight, history of allergies, and the likelihood of colonization by resistant bacteria should be considered. Compliance with institutional protocols enhances the effectiveness of antibiotic use. Surgical antibiotic prophylaxis is associated with reduced rates of surgical site infection, hospital stay, and morbimortality.