The emergent invasive serotype 4 ST10172 strain acquires vanG type vancomycin-resistance element: A case of a 66-year-old with bacteremic pneumococcal pneumonia.

We report a single case of invasive pneumococcal disease (IPD) by serotype 4, multilocus sequence type 10172 (serotype 4/ST10172) isolate with vanG-type resistance genes and reduced vancomycin susceptibility. The isolate was recovered during 2022 from a 66-year-old resident with bacteremic pneumococcal pneumonia within a CDC Active Bacterial Core surveillance (ABCs) site hospital. The patient had received 23-valent pneumococcal polysaccharide vaccine and there was no evidence of concurrent or prior receipt of vancomycin in the previous year. Serotype 4/ST10172 IPD has shown increases within western ABCs sites and the recent acquisition of a vanG element warrants close monitoring of this lineage.

A Skin Testing Strategy for Non-IgE-mediated Reactions Associated with Vancomycin.

BACKGROUND: Vancomycin infusion reaction (VIR), reportedly mediated through Mas-Related G Protein-Coupled Receptor-X2 (MRGPRX2), is the primary vancomycin-induced immediate drug reaction (IDR). Clinically, distinguishing the underlying drug-induced IDR mechanisms is crucial for future treatment strategies, including drug restriction, re-administration, and pretreatment considerations. However, the lack of validated diagnostic tests makes this challenging, often leading to unnecessary drug restriction. OBJECTIVE: To determine if intradermal tests (IDTs) and, separately, the basophil activation test (BAT) differentiate VIR from vancomycin-tolerant subjects. METHODS: Cross-sectional study of vancomycin-exposed adults with and without a history of VIR. Demographics, allergy-related comorbidities, history of vancomycin exposures, and VIR characteristics were collected. IDT with vancomycin was performed. IDT dose responses EC50, IDT-related local symptoms, and BAT were compared between groups. RESULTS: 11 VIR and 10 vancomycin-tolerant subjects were enrolled. The most reported VIR symptoms were pruritus (82%), flushing (82%), hives (46%), hives (46%), angioedema (27%), and dyspnea (19%). The IDT dose response mean EC50 was 328 µg/mL (95% CI 296, 367) in the VIR vs. 1,166 µg/mL (95% CI 1029, 1379) in the tolerant group (p<0.0001). All VIR subjects reported IDT-related local pruritus compared to 60% of tolerant subjects (p=0.0185). The %CD63+ basophils were consistently <2%, without significant differences between groups (p < 0.54). CONCLUSIONS: Variations in skin test methodologies could help identify other IDR mechanisms beyond IgE. This skin test protocol holds the potential for identifying VIR, particularly in cases where patients have received multiple drugs while BAT is insufficient. Future studies will validate and delineate its predictive value, assessing the risk of VIR.

Comparison of the Areas Under the Curve of Vancomycin Continuous vs. Intermittent Infusion in Critically Ill Pediatrics: A Randomized Clinical Trial.

Background: Providing data on the superior efficacy of vancomycin administered based on the area under the curve over 24 hours to the minimum inhibitory concentration of vancomycin (AUC24/MIC) is crucial. However, data on dosing and monitoring of vancomycin pharmacokinetics in the pediatric population are limited. Previous findings have showed that intermittent infusion of vancomycin (IIV) may not achieve the desired levels, continous infusions of vancomycin (CIV) reach the desired serum concentration faster than IIV and are associated with reduced nephrotoxicity. Objectives: This study aimed to compare the serum concentrations, AUC24, clinical variables, and adverse effects of two vancomycin administration methods in the pediatric population. Methods: This study was a double-blind, randomized, controlled clinical trial conducted at a tertiary children's teaching hospital. Inclusion criteria were age between 2 months and 15 years and weight less than 67 kilograms, with exclusion criteria including renal impairment. Participants were divided into CIV and IIV groups following distinct administration protocols. Demographic, clinical, and laboratory data, including vancomycin serum concentrations, were compiled. Assessments included pediatric mortality risk, pediatric sequential organ failure assessment, and regular temperature monitoring. Pharmacokinetic analysis was conducted using Monolix software 2023R1. Primary endpoints were vancomycin serum levels and AUC24 between cohorts on day three, with nephrotoxicity and additional adverse drug responses evaluated. Results: Sixty-eight patients in the pediatric intensive care unit (PICU) were allocated to either CIV (33) or IIV (35) for vancomycin treatment. In the CIV group, 82% of patients achieved an AUC24 ≥ 400 mg.h/L, compared to 23% in the IIV group. Continuous infusions of vancomycin demonstrated a greater AUC24 (587.7 ± 184.4 mg.h/L vs. 361.9 ± 113.2 mg.h/L, P < 0.05) compared to IIV. Two cases of nephrotoxicity were reported, one in each group, with mortality and adverse events being comparable between the two groups. Conclusions: This study demonstrated that continuous vancomycin infusion has a higher success rate in safely achieving therapeutic vancomycin levels in PICU patients compared to intermittent vancomycin infusion.

A Report of a Rare Case of Kounis Syndrome in a Patient With HIV/AIDS and Mpox.

Kounis syndrome (KS) is defined as the occurrence of acute coronary syndrome due to coronary artery spasm in a patient with an allergic reaction. Antibiotics are the most common trigger for KS. In this case report, we present a 45-year-old man with HIV/AIDS who was being managed for mpox and developed chest pain and hypotension during vancomycin infusion, which was complicated by the development of ST-elevation myocardial infarction (STEMI). His left heart catheterization showed normal coronaries with the resolution of ECG changes and symptoms upon discontinuing vancomycin.

Does the removal of isolation for VRE infected patients change the incidence of healthcare-associated VRE?: A systematic review and meta-analysis.

BACKGROUND: Several single-center studies have suggested that eliminating isolation for vancomycin-resistant enterococci (VRE) control in the context of endemic or non-outbreak settings, has no impact on infection rates. We performed a systematic review and meta-analysis on the impact of discontinuing isolation. METHODS: We searched PubMed, Embase, the Cochrane Library and Web of Science through April 10, 2024 for studies evaluating discontinuation of isolation for VRE. Subgroup analyses assessed sources of heterogeneity. RESULTS: Nine studies were included in the final review. Four reported the incidence of hospital-acquired VRE (HA-VRE) infections and five reported the incidence of hospital-acquired VRE bloodstream infections (HA-VRE BSI). No significant difference between rates of HA-VRE infection before and after stopping isolation was observed (RR, 0.93; 95% CI, 0.68-1.26; P = 0.62), as well as no significant difference on the incidence of HA-VRE BSI (RR, 0.68; 95% CI, 0.44-1.07, P = 0.09). Furthermore, we conducted two subgroup analyses: one stratified by whether the studies were conducted during COVID-19, and the other stratified by whether clinicians continued to use personal protective equipment. Both analyses revealed no significant differences in the incidence of HA-VRE BSI and termination of isolation between the subgroups. CONCLUSION: In the context of endemic or non-outbreak settings, discontinuation of isolation for VRE patients has not been associated with an increased rate of HA-VRE infections.

Teicoplanin in peritoneal dialysis: efficacy, safety, and pharmacological considerations.

Peritoneal dialysis (PD) is a vital treatment modality for renal failure patients, facilitating the removal of excess fluid and unwanted substances. However, peritonitis, a significant complication experienced by PD patients, necessitates careful selection of antibiotics to ensure successful treatment. Commonly used antibiotics in PD patients, such as cephalosporins and glycopeptides like vancomycin, have been associated with undesirable side effects and high failure rates. In response to these challenges, teicoplanin, a novel glycopeptide antibiotic, has gained attention due to its similar range of activity to vancomycin, extended half-life, reduced side effects, and improved elimination. The objective of this study is to comprehensively review the efficacy, mechanism of action, adverse effects, and pharmacological benefits of teicoplanin in peritoneal dialysis patients. Our research involved an extensive review of 21 articles from reputable databases, including Google Scholar, PubMed, and ScienceDirect. The data extracted from these studies was meticulously evaluated to comprehensively understand teicoplanin's clinical profile in this specific patient population. Major findings of these studies are that glycopeptide-based regimens have higher cure rates over first-generation cephalosporins or fluoroquinolones, and teicoplanin demonstrated several advantages over vancomycin, such as a higher therapeutic index, good tolerance, longer half-life, lower rates of nephrotoxicity, improved elimination while being equally effective. Teicoplanin is typically administered to peritoneal dialysis patients with a loading dose of 400 mg, aiming to achieve a trough concentration of 10-15 mg/dl. Teicoplanin's improved tolerability and lack of regular serum level monitoring requirements make it a promising alternative to traditional antibiotics for clinical use.

Comparison of the Effect of Different Treatment Doses of Intrastromal Vancomycin in a Rabbit Model of Methicillin-Resistant Staphylococcus Aureus (MRSA) Keratitis.

PURPOSE: To compare the effect of different doses of vancomycin on a rabbit model of MRSA keratitis. METHODS: Twenty-four eyes of 24 New-Zealand White rabbits were included in the study. MRSA keratitis was applied to 24 left eyes of 24 New Zealand rabbits. Twenty-four hours after MRSA inoculation; 0.5 mg/0.1 mL, 1 mg/0.1 mL, and 2 mg/0.1 mL and balanced salt solution were administered to 6 rabbits in 4 groups, respectively. RESULTS: The effect of different doses of vancomycin on reducing bacterial load was found to be statistically significant when each was compared to the control group (p = 0.006). When comparing the dosages with each other, no superiority was shown (p = 0.297, p = 0.749, p = 0.262 respectively). There was a significant increase in the posttreatment total clinical score in the control and 2 mg/0.1 mL groups compared to the pretreatment score (p = 0.001, p = 0.001 respectively). CONCLUSION: It is emphasized that necessary treatment can be achieved by administering less antibiotic (0.5 mg/0.1 mL) to the corneal intrastromal area.

Effect of Topical Vancomycin on Surgical Site Infections in Ankle Fractures: A Randomized, Double-Blind, Controlled Trial.

Background Applying topical vancomycin has shown a decrease in the likelihood of surgical site infections (SSIs) in surgeries linked to a heightened risk of severe and resistant infections. Nevertheless, the effectiveness of this prophylactic approach has not been assessed in open ankle surgeries with internal fixation. Objective This study aimed to assess whether topical vancomycin diminishes the risk of SSI in patients with ankle fractures undergoing open reduction with internal fixation. Methods A randomized, controlled, double-blind clinical trial was carried out. Patients were divided into two groups in a 1:1 ratio. The control group received the standard prophylactic treatment with IV cephalothin 1 g, while the intervention group was administered topical vancomycin (1 g) in addition to the standard prophylactic treatment. The main outcomes were the SSI rates at 14 days, 28 days, and three months post-surgery, based on relevant clinical signs and laboratory tests. Results One hundred thirty-two patients were randomized (51.2% female), with 66 subjects included in each intervention arm. A total of 97.7% of them completed the study. Both groups were homogeneous in baseline characteristics. There were two SSIs in both the vancomycin group (3.3%) and the control group (3.5%), with no statistical differences (p = 0.945). The microorganisms isolated as causal agents were Staphylococcus aureus and Acinetobacter baumannii. By the three-month follow-up, no infections were noted in both intervention groups. Conclusion These results indicate that the topical administration of vancomycin may not represent an advantage in preventing SSI in ankle fractures requiring open reduction with internal fixation at the three-month postoperative stage.

Risk Factors for Surgical Site Infections and the Effects of Betadine Irrigation and Intrawound Vancomycin Powder on Infection Rates in Spine Tumor Surgery.

Background Surgical site infection (SSI) following spine tumor surgery results in delays in radiation therapy and the initiation of systemic treatment. The study aims to assess risk factors for SSI in malignancy-related spinal infections and rates of infection observed in a single center with the use of betadine irrigation (BI) and intrawound vancomycin powder (IVP).  Methods Spine tumor patients managed from 11/2012 to 11/2023 were identified using a surgical database (JotLogs, Efficient Surgical Apps, Portland, Maine). Inclusion criteria were patients receiving BI and IVP and alive at 30 days post-op. Exclusion criteria were patients not receiving a combination of BI and IVP due to allergies and mortality within 30 days of surgery. Patient demographics, histology, history of pre-operative and post-operative radiation treatment history, tumor location, procedure type, number of procedures per patient, SSI, wound culture results, and mortality were collected. Results One hundred two patients undergoing 130 procedures had an SSI rate of 3.85% (5/130). There were 18.6% primary and 81.4% metastatic tumors. Demographics were average age 59.5 years old (range 7-92), 60.8% male, 39.2% female, White 88.2%, Black 9.8%, and others 2%. Pre-operative radiation therapy was significantly associated with the risk of SSI (p=0.005). Percutaneous instrumentation did not lead to a significant difference in infection rates (p=0.139). There was no significant difference in infection rates between primary and metastatic tumors (p=0.58). Multivariable regression analysis revealed pre-operative radiation (OR: 18.1; 95%CI: 1.9-172.7; p=0.009) as the statistically significant independent risk factor. Conclusions Pre-operative radiation therapy remains a risk factor for SSI. However, percutaneous instrumentation did not lead to SSI, and there was no significant difference in infection rates between primary and metastatic tumors. SSI rate was 3.85% in patients who had a combination of BI and IVP in spine tumor surgery.

A Comparison of Sequelae After a Practice Change From Vancomycin to Ampicillin Containing Antibiotic Regimens for Necrotizing Enterocolitis.

The aim of this study was to compare sequelae and acute kidney injury (AKI) occurrence among patients with necrotizing enterocolitis (NEC) after changing institutional guidelines replacing vancomycin with ampicillin for gram-positive coverage. This was a retrospective, single-center cohort analysis of patients from 2016-2020 (n = 73) with NEC at a surgical neonatal intensive care unit with a high community prevalence of methicillin-resistant Staphylococcus aureus (MRSA). Multivariate logistic regression was utilized to assess associations. Twenty-five (34%) patients had at least 1 sequela related to NEC. Ampicillin containing regimens were not associated with any sequelae type or AKI. Postmenstrual age < 29 weeks at diagnosis ([OR] 5.8 [1.2-28.8], P = .03; and receipt of vasopressors [OR] 3.3 [1.1-10.2], P = .04) were independently associated with sequalae. Stage III NEC was independently associated with AKI, OR 10.6 (2-55.6), P = .005. In conclusion, ampicillin-containing regimens are effective for NEC management at our institution despite a high prevalence of MRSA.

COMPLICATIONS OF INTRAOSSEOUS ADMINISTRATION OF VANCOMYCIN IN TOTAL HIP ARTHROPLASTY. / COMPLICACIONES DE LA ADMINISTARCION INTRAOSEA DE VANCOMICINA EN ARTROPLASTIA TOTAL DE CADERA.

INTRODUCTION: The incidence of periprosthetic joint infection (PJI) in hip surgeries has significantly decreased thanks to intravenous antibiotic prophylaxis. However, in patients colonized with methicillin-resistant Staphylococcus aureus (MRSA) or those at risk of colonization, it is necessary to include vancomycin in the prophylaxis. Intraosseous (IO) administration of vancomycin could enhance its effectiveness in total hip arthroplasty (THA). MATERIALS AND METHODS: A retrospective study was conducted between March and December 2023 involving 53 patients scheduled for primary THA with colonization risk factors. The median age of the patients was 67 years (range 61 to 75), and all received treatment with intraosseous vancomycin (500 mg). Detailed records and documentation of complications during hospitalization and the first three months post-surgery were maintained. As a secondary outcome measure, the incidence of PJI was explored. RESULTS: We administered 500 mg of intraosseous vancomycin, injected into the greater trochanter, along with standard intravenous (IV) prophylaxis. The incidence of complications was 1.64%. The periprosthetic joint infection rate at 90 days was 0%. CONCLUSIONS: Intraosseous administration of low-dose vancomycin in total hip arthroplasty for patients at risk of MRSA colonization, combined with standard IV prophylaxis, was shown to be safe and did not present significant adverse effects. Furthermore, this strategy eliminates the logistical challenges associated with timely vancomycin administration. LEVEL OF EVIDENCE IV: Case Series.

Metabolomic analysis in Amycolatopsis keratiniphila disrupted the competing ECO0501 pathway for enhancing the accumulation of vancomycin.

Vancomycin is a clinically important glycopeptide antibiotic against Gram-positive pathogenic bacteria, especially methicillin-resistant Staphylococcus aureus. In the mutant strain of Amycolatopsis keratiniphila HCCB10007 Δeco-cds4-27, the production of ECO-0501 was disrupted, but enhanced vancomycin yield by 55% was observed compared with the original strain of A. keratiniphila HCCB10007. To gain insights into the mechanism of the enhanced production of vancomycin in the mutant strain, comparative metabolomics analyses were performed between the mutant strain and the original strain, A. keratiniphila HCCB10007 via GC-TOF-MS and UPLC-HRMS. The results of PCA and OPLS-DA revealed a significant distinction of the intracellular metabolites between the two strains during the fermentation process. 64 intracellular metabolites, which involved in amino acids, fatty acids and central carbon metabolism, were identified as differential metabolites. The high-yield mutant strain maintained high levels of glucose-1-phosphate and glucose-6-phosphate and they declined with the increases of vancomycin production. Particularly, a strong association of fatty acids accumulation as well as 3,5-dihydroxyphenylacetic acid and non-proteinogenic amino acid 3,5-dihydroxyphenylglycine (Dpg) with enhancement of vancomycin production was observed in the high-yield mutant strain, indicating that the consumption of fatty acid pools might be beneficial for giving rise to 3,5-dihydroxyphenylacetic acid and Dpg which further lead to improve vancomycin production. In addition, the lower levels of glyoxylic acid and lactic acid and the higher levels of sulfur amino acids might be beneficial for improving vancomycin production. These findings proposed more advanced elucidation of metabolomic characteristics in the high-yield strain for vancomycin production and could provide potential strategies to enhance the vancomycin production.

Comparative effectiveness of vancomycin and metronidazole on event-free survival after initial infection in patients with Clostridioides difficile - a German multicentre cohort study (IBIS).

OBJECTIVES: The objective of this study is to examine the comparative effectiveness of vancomycin and metronidazole in a confirmatory analysis of event-free survival (EFS) following initial infection in patients with Clostridioides difficile (C. difficile) from a German multicentre cohort study. METHODS: The IBIS multicentre cohort enrolled patients with an index episode of CDI between August 2017 and September 2020. The primary endpoint was EFS, defined as response to treatment with metronidazole or vancomycin within ten days of initiation, absence of recurrence and death from any cause up to 90 days post-treatment. A Cox proportional hazards model with inverse probability of treatment weighting was used to investigate the comparative effectiveness of this outcome. Additionally, subgroup analyses were performed based on severe and non-severe infections. RESULTS: Of the 489 patients included, 118 (24%) received initial treatment with metronidazole and 371 (76%) with vancomycin. Of these, 78/118 (66.1%) and 247/371 (66.6%), respectively, responded to treatment within ten days, neither developed a recurrence nor died within 90 days and thus achieved the outcome of EFS. In the subgroup of non-severe infections, 74/293 patients (25.3%) received metronidazole, and 219/293 (74.7%) received vancomycin. Of these, 33/74 (44.6%) metronidazole patients and 150/219 (68.5%) vancomycin patients survived event-free. The Cox proportional hazards model revealed differences in EFS for the overall population and both sub-groups (reference metronidazole: all severity levels: hazard ratio [HR] 0.46, [95% Cl 0.33-0.65]; non-severe: HR 0.39; [95% Cl 0.24-0.60]; severe: HR 0.52; [95% Cl 0.28-0.95]). CONCLUSIONS: Our analysis confirms current changes in guidelines, as it supports the superiority of vancomycin compared to metronidazole across all severity levels.

Recent advances in nanostructured delivery systems for vancomycin.

Despite the development of new generations of antibiotics, vancomycin remained as a high-efficacy antibiotic for treating the infections caused by MRSA. Researchers have explored various nanoformulations, aiming to enhance the therapeutic efficacy of vancomycin. Such novel formulations improve the effectiveness of drug cargoes in treating bacterial infections and minimizing the risk of adverse effects. The vast of researches have focuses on enhancing the permeation ability of vancomycin through different biological barriers especially those of gastrointestinal tract. Increasing the drug loading and tuning the drug release from nanocarrier are other important goal for many conducted studies. This study reviews the newest nano-based formulations for vancomycin as a key antibiotic in treating hospitalized bacterial infections.

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Early identification of the nosocomial spread of vancomycin-resistant Enterococcus faecium by Fourier-transform infrared spectroscopy and performance comparison with PFGE and WGS.

Early detection of disseminating vancomycin-resistant Enterococcus faecium (VREfm) in ICU wards is crucial for outbreak identification and the implementation of prompt infection control measures. Genotypic methods like pulsed-field gel electrophoresis (PFGE) and whole-genome sequencing (WGS) are costly and time-consuming, hindering rapid response due to batch dependency. Fourier-transform infrared spectroscopy (FT-IR) offers potential for real-time outbreak detection and reliable strain typing. We utilized FT-IR to identify clonal VREfm dissemination and compared its performance to PFGE and WGS. Between February through October 2023, an unusually high number of VREfm were recovered at a tertiary hospital in Barcelona. Isolates were examined for antimicrobial susceptibility, carriage of vanA/vanB genes and clonality was also studied using FT-IR, PFGE, and WGS. Routine FT-IR inspections revealed recurring VREfm clustering during the outbreak's initial weeks. In total, 104 isolates were recovered from 75 patients and from multiple wards. However, only one isolate was recovered from an environmental sample, suggesting the absence of environmental reservoirs. An ST80 vancomycin-resistant (vanA) E. faecium strain was the main strain responsible for the outbreak, although a few additional VREfm strains were also identified, all belonging to CC17. PFGE and cgMLST (WGS) yielded identical clustering results to FT-IR, and WGS confirmed vanA/vanB gene carriage in all VREfm isolates. Infection control measures led to a rapid decline in VREfm isolates, with no isolates detected in November. FT-IR spectroscopy offers rapid turnaround times, sensitivity, and reproducibility, comparable to standard typing methods. It proved as an effective tool for monitoring VREfm dissemination and early outbreak detection.

Presoaking hamstring autograft with vancomycin does not jeopardize its biomechanical properties, including graft elongation, after cyclic loading.

PURPOSE: Presoaking the graft with vancomycin before implantation has been shown to reduce the risk of postoperative infection after anterior cruciate ligament reconstruction (ACLR). However, the effects of presoaking on the graft biomechanical properties remain unclear. This study aimed to determine whether presoaking the graft with vancomycin affects the graft biomechanical properties and length after cyclic loading. METHODS: Ten paired (20 specimens) gracilis and semitendinous tendons were harvested from fresh-frozen human cadaveric specimens. Two tendons were folded in half to make four strands, and the grafts were randomized into the vancomycin and control groups. The graft was exposed to the antibiotic solution for 15 min (5 mg/mL) and prepared by mixing 1 g of vancomycin with 200 mL of normal saline (NaCl 0.9%). The control group was soaked in normal saline for 15 min. The prepared grafts were attached to the actuator of a dynamic tensile-testing machine. All grafts were tested with 3000 cycles of cyclic loading followed by a pull-to-failure. The cyclic loading protocol consisted of position and load control blocks to simulate the graft in vivo in the postoperative phase after ACLR. RESULTS: Presoaking in vancomycin did not jeopardize the biomechanical properties of the graft. In addition, presoaking with vancomycin did not elongate the grafts. No significant differences were found in the mean Young's modulus and the mean total elongation of the graft of the specimen between the vancomycin group and the control group. CONCLUSION: Presoaking the graft with vancomycin jeopardized neither its biomechanical properties nor elongation even after cyclic loading in this in vitro study. It is suggested that vancomycin presoaking could be considered a safe and effective preventive measure for postoperative infections after ACLR. LEVEL OF EVIDENCE: Not applicable.

Risk factors analysis and construction of predictive models for acute kidney injury in overweight patients receiving vancomycin treatment.

BACKGROUND: Vancomycin induced acute kidney injury (VI-AKI) is one of its serious adverse reactions. The purpose of this study is to discuss the risk factors for VI-AKI in overweight patients and construct a clinical prediction model based on the results of the analysis. METHODS: Multivariable logistic regression analysis was used to identify risk factors for VI-AKI and constructed nomogram models. The performance of the nomogram was evaluated based on the area under the receiver operating characteristic curve (AUC), calibration curves and decision curve analysis (DCA). RESULT: Cancer (OR 4.186, 95% CI 1.473-11.896), vancomycin trough concentration >20.0 µg/mL (OR 6.251, 95% CI 2.275-17.180), concomitant furosemide (OR 2.722, 95% CI 1.071-6.919) and vasoactive agent (OR 2.824, 95% CI 1.086-7.340) were independent risk factors for VI-AKI. The AUC of the nomogram validation cohorts were 0.807 (95% CI 0.785-0.846). The calibration curve revealed that the predicted outcome was in agreement with the actual observations. Finally, the DCA curves showed that the nomogram had a good clinical applicability value. CONCLUSION: There are four independent risk factors for the occurrence of VI-AKI in overweight patients, and the nomogram prediction model has good predictive ability, which can provide reference for clinical decision-making.

Symbiotic biofilms formed by Clostridioides difficile and bacteroides thetaiotaomicron in the presence of vancomycin.

Vancomycin (VAN) treatment in Clostridioides difficile infection (CDI) suffers from a relatively high rate of recurrence, with a variety of reasons behind this, including biofilm-induced recurrent infections. C. difficile can form monophyletic or symbiotic biofilms with other microbes in the gut, and these biofilms protect C. difficile from being killed by antibiotics. In this study, we analyzed the ecological relationship between Bacteroides thetaiotaomicron and C. difficile and their formation of symbiotic biofilm in the VAN environment. The production of symbiotic biofilm formed by C. difficile and B. thetaiotaomicron was higher than that of C. difficile and B. thetaiotaomicron alone in the VAN environment. In symbiotic biofilms, C. difficile was characterized by increased production of the toxin protein TcdA and TcdB, up-regulation of the expression levels of the virulence genes tcdA and tcdB, enhanced bacterial cell swimming motility and c-di-GMP content, and increased adhesion to Caco-2 cells. The scanning electron microscope (SEM) combined with confocal laser scanning microscopy (CLSM) results indicated that the symbiotic biofilm was elevated in thickness, dense, and had an increased amount of mixed bacteria, while the fluorescence in situ hybridization (FISH) probe and plate colony counting results further indicated that the symbiotic biofilm had a significant increase in the amount of C. difficile cells, and was able to better tolerate the killing of the simulated intestinal fluid. Taken together, C. difficile and B. thetaiotaomicron become collaborative in the VAN environment, and targeted deletion or attenuation of host gut B. thetaiotaomicron content may improve the actual efficacy of VAN in CDI treatment.

Highly sensitive SERS nanoplatform based on aptamer and vancomycin for detection of S. aureus and its clinical application.

Staphylococcus aureus (S. aureus) is the most common pathogen in human purulent infections, which can cause local purulent infections, as well as pneumonia, pseudomembranous enteritis, pericarditis, and even systemic infections. The conventional methods including bacteria colony counting, polymerase chain reaction and enzyme-linked immunosorbent assay can't fully meet the requirement of highly sensitive detection of S. aureus due to their own disadvantages. Therefore, it's an urgent need to develop new platform to detect S. aureus in the early infection stage. In this study, a new surface-enhanced Raman scattering (SERS)-based nanoplatform based on dual-recognition of aptamer (Apt) and vancomycin (Van) was developed for the highly sensitive detection of S. aureus. The SERS nanoplatform consisted of two functional parts: aptamer-conjugated Fe3O4 magnetic nanoparticles (Fe3O4-Apt MNPs) for bacteria enrichment and vancomycin modified-Au nanoparticles (Van-Au NPs) as the SERS probes for S. aureus quantitative detection. Upon the target bacteria enrichment, the SERS signals of the supernatant after magnetic separation could be obtained and analyzed under different concentrations of S. aureus. The limit of detection of the proposed assay was found to be 3.27 CFU/mL. We believe that the proposed SERS-based nanoplatform has great potential as a powerful tool in the early detection of specific bacteria.