Antimicrobial Treatment Duration in Sepsis and Serious Infections

Investigation of the Significance of Blood Signatures on Sepsis-Induced Acute Lung Injury in Sepsis Within 24 Hours

Background: Sepsis is an infection-induced dysregulated cellular response that leads to multiorgan dysfunction. As a time-sensitive condition, sepsis requires prompt diagnosis and standardized treatment. This study investigated the impact of biomarkers identified in peripheral whole blood from sepsis patients (24-h post-onset) on sepsis-induced acute lung injury (ALI) using bioinformatics and machine learning approaches. Methods: Gene Expression Omnibus (GEO) datasets were analyzed for functional and differential gene expression. Critical genetic markers were identified and evaluated using multiple machine learning algorithms. Single-cell RNA sequencing (scRNA-seq) and cell-type identification by estimating relative subsets of RNA transcript (CIBERSORT) were conducted to explore associations between biomarkers and immune cells. Biomarker expression was further validated through animal experiments. Result: A total of 611 overlapping differentially expressed genes (DEGs) were identified in GSE54514, including 361 upregulated and 250 downregulated genes. From GSE95233, 1150 DEGs were detected, with 703 upregulated and 447 downregulated genes. Enrichment analysis revealed DEGs associated with immune cell activity, immune cell activation, and inflammatory signaling pathways. Component 3a receptor 1 (C3AR1) and secretory leukocyte peptidase inhibitor (SLPI) were identified as critical biomarkers through multiple machine learning approaches. CIBERSORT analysis revealed significant associations between immune cell types and C3AR1/SLPI. Moreover, the scRNA-seq analysis demonstrated that the SLPI expression was significantly elevated in immunological organ cells during the early stages of sepsis, a finding further validated in sepsis-induced ALI models. Conclusion: This study employed machine learning techniques to identify sepsis-associated genes and confirmed the importance of SLPI as a biomarker within 24 h of sepsis onset. SLPI also played a significant role in sepsis-induced ALI, suggesting its potential as a novel target for personalized medical interventions, targeted prevention, and patient screening.

Association Between In-Hospital Antibiotic Use and Long-Term Outcomes in Critically Ill Patients

Objective

To assess whether antibiotic duration (AD) and one-year antibiotic-free days (AFD) are associated with key in-hospital and post-discharge outcomes among critically ill adults.

Design

Retrospective observational study.

Setting

Quaternary care academic medical center in the United States.

Patients

A total of 126 critically ill adults, mean age 68.1 years (±15.6), 51.6% male, median APACHE II score of 20.5 (IQR 15-25); 71.4% met sepsis criteria.

Methods

Patient demographics, clinical characteristics, antibiotic use, and outcomes were collected over one year. Secondary infection was defined as ≥3 consecutive antibiotic days within a year following the index sepsis admission. Multivariate analyses adjusted for age, APACHE II score, gender, and glucocorticosteroid dose.

Results

Within 30 days, longer AD correlated with increased hospital stay (p<0.001) with each additional day of antibiotics associated with 0.37 - 0.39 extra days of hospitalization in univariate and multivariate analyses, respectively. In septic patients specifically, AFD significantly correlated with hospital length-of-stay in both univariate (p=0.023) and multivariate analyses (p=0.002), with no impact from infection type on AD or AFD. Fewer AFD correlated with higher secondary bacteremia rates in unadjusted analysis (p=0.023 overall), but this effect was not significant after multivariable adjustment. Neither AD nor AFD predicted one-year mortality or readmission.

Conclusions

Extended antibiotic duration in critically ill patients prolonged hospital stays without providing mortality or readmission benefits. These findings underscore the importance of robust antibiotic stewardship, where shorter, targeted regimens can reduce unintended complications and improve overall outcomes.

Antibiotic-Modified Nanoparticles Combined with Lysozyme for Rapid Extraction of Pathogenic Bacteria DNA in Blood

Rapid and precise identification of the pathogens causing sepsis remains a significant diagnostic challenge. Blood culture is time-consuming and insensitive, while molecular diagnostic techniques, such as the polymerase chain reaction (PCR), are fast but greatly influenced by template quality. Here, we present a new approach to separate trace amounts of pathogen DNA from blood, which utilizes lysozyme to destroy bacteria and release DNA, followed by enrichment and purification using magnetic nanoparticles (MNPs) modified with kanamycin (Kan) or tobramycin (TM). We demonstrate that the prepared Kan@MNPs and TM@MNPs can efficiently adsorb DNA, with the mechanism involving interaction with the minor groove of DNA. Notably, the adoption of lysozyme ensures bacterial lysis while avoiding damage to blood cells, minimizing the interference from human genomic DNA background and inhibitory components, thereby obtaining relatively pure bacterial DNA. For artificially infected whole blood samples, our method shortens the sample processing time to 35 min and achieves a 10-fold improvement in PCR sensitivity compared to a commercial kit. Through clinical evaluation of blood samples collected from suspected infected patients, we identified positive samples that were 100% consistent with the clinical practice. Therefore, this method holds promising potential for clinical application in advancing rapid sepsis diagnosis and earlier interventions.

Exploring the Impact of Chemotherapy on the Emergence of Antibiotic Resistance in the Gut Microbiota of Colorectal Cancer Patients

With nearly half of colorectal cancer (CRC) patients diagnosed at advanced stages where surgery alone is insufficient, chemotherapy remains a cornerstone for this cancer treatment. To prevent infections and improve outcomes, antibiotics are often co-administered. However, chemotherapeutic interactions with the gut microbiota cause significant non-selective toxicity, affecting not only tumor and normal epithelial cells but also the gut microbiota. This toxicity triggers the bacterial SOS response and loss of microbial diversity, leading to bacterial mutations and dysbiosis. Consequently, pathogenic overgrowth and systemic infections increase, necessitating broad-spectrum antibiotics intervention. This review underscores how prolonged antibiotic use during chemotherapy, combined with chemotherapy-induced bacterial mutations, creates selective pressures that drive de novo antimicrobial resistance (AMR), allowing resistant bacteria to dominate the gut. This compromises the treatment efficacy and elevates the mortality risk. Restoring gut microbial diversity may mitigate chemotherapy-induced toxicity and improve therapeutic outcomes, and emerging strategies, such as fecal microbiota transplantation (FMT), probiotics, and prebiotics, show considerable promise. Given the global threat posed by antibiotic resistance to cancer treatment, prioritizing antimicrobial stewardship is essential for optimizing antibiotic use and preventing resistance in CRC patients undergoing chemotherapy. Future research should aim to minimize chemotherapy's impact on the gut microbiota and develop targeted interventions to restore microbial diversity affected during chemotherapy.

The Therapeutic Potential of Exosome Therapy in Sepsis Management: Addressing Complications and Improving Outcomes"

Infection occurs when pathogens penetrate tissues, reproduce, and trigger a host response to both the infectious agents and their toxins. A diverse array of pathogens, including viruses and bacteria, can cause infections. The host's immune system employs several mechanisms to combat these infections, typically involving an innate inflammatory response. Inflammation is a complex biological reaction that can affect various parts of the body and is a key component of the response to harmful stimuli. Sepsis arises when the body's response to infection leads to widespread damage to tissues and organs, potentially resulting in severe outcomes or death. The initial phase of sepsis involves immune system suppression. Early identification and targeted management are crucial for improving sepsis outcomes. Common treatment approaches include antibiotics, intravenous fluids, blood cultures, and monitoring urine output. This study explores the potential of exosome therapy in enhancing the management and alleviation of sepsis symptoms.

Agar-Dilution Is Comparable to Broth Dilution for MIC Determination in Streptococcus agalactiae

BACKGROUND

Streptococcus agalactiae (Group B Streptococcus, GBS) is a leading cause of neonatal sepsis in high-income countries. While intrapartum antibiotic screening reduces this risk, increasing resistance to macrolides and lincosamides in Europe since the 1990s has limited therapeutic options for penicillin-allergic patients. Reports of reduced beta-lactam susceptibility in GBS further emphasise the need for robust antimicrobial resistance (AMR) surveillance. However, broth microdilution (BMD) methods are unsuitable for large-scale antimicrobial susceptibility testing (AST).

OBJECTIVE

To demonstrate that agar-dilution AST provides equivalent results to broth dilution methods, with superior capacity for high-throughput screening.

METHODS

Agar-dilution and microdilution AST methods were compared using a panel of 24 characterised susceptible and resistant GBS strains for benzylpenicillin, chloramphenicol, clindamycin, erythromycin, gentamicin, levofloxacin, tetracycline, and vancomycin. Minimum inhibitory concentration (MIC) agreements were evaluated, and resistance profile correlations were assessed using Cohen's kappa values.

RESULTS

Agar-dilution demonstrated >90% agreement with BMD MIC for most antimicrobials, except vancomycin (87.5%), erythromycin (83.33%), and tetracycline (52.78%). Cohen's kappa values indicated strong agreement (0.88-1.00) for resistance determination. Agar-dilution avoided "trailing growth" issues associated with BMD and facilitated easier detection of non-GBS contaminants.

CONCLUSIONS

Agar-dilution is a valid method for high-throughput AMR surveillance of retrospective cohorts (96 isolates per plate) and is critical for identifying emerging GBS resistance trends and informing therapeutic guidelines. However, due to the large number of plates required per antimicrobial, it is impractical for routine clinical diagnostics.

Ceftazidime/avibactam versus polymyxin B in carbapenem-resistant Klebsiella pneumoniae infections: a propensity score-matched multicenter real-world study

OBJECTIVES

In this retrospective observational multicenter study, we aimed to assess efficacy and mortality between ceftazidime/avibactam (CAZ/AVI) or polymyxin B (PMB)-based regimens for the treatment of Carbapenem-resistant Klebsiella pneumoniae (CRKP) infections, as well as identify potential risk factors.

METHODS

A total of 276 CRKP-infected patients were enrolled in our study. Binary logistic and Cox regression analysis with a propensity score-matched (PSM) model were performed to identify risk factors for efficacy and mortality.

RESULTS

The patient cohort was divided into PMB-based regimen group (n = 98, 35.5%) and CAZ/AVI-based regimen group (n = 178, 64.5%). Compared to the PMB group, the CAZ/AVI group exhibited significantly higher rates of clinical efficacy (71.3% vs. 56.1%; p = 0.011), microbiological clearance (74.7% vs. 41.4%; p < 0.001), and a lower incidence of acute kidney injury (AKI) (13.5% vs. 33.7%; p < 0.001). Binary logistic regression revealed that the treatment duration independently influenced both clinical efficacy and microbiological clearance. Vasoactive drugs, sepsis/septic shock, APACHE II score, and treatment duration were identified as risk factors associated with 30-day all-cause mortality. The CAZ/AVI-based regimen was an independent factor for good clinical efficacy, microbiological clearance, and lower AKI incidence.

CONCLUSIONS

For patients with CRKP infection, the CAZ/AVI-based regimen was superior to the PMB-based regimen.

Biomarker for infection in children with decompensated chronic liver disease: Neutrophilic CD64 or procalcitonin?

OBJECTIVE

Biomarkers with high accuracy for identification of infection in decompensated chronic liver disease (DCLD) are urgently needed. We compared the accuracy of neutrophilic cluster of differentiation 64 (nCD64) with procalcitonin for diagnosis of bacterial infection in children with DCLD.

METHODS

Consecutive children admitted with DCLD were enrolled prospectively. nCD64 was assessed by flow cytometry and expressed in percentage. nCD64, procalcitonin and hemogram were measured at admission and 7-14 days after treatment in those with infection. Complete work-up for infection was done. Presence, site and severity of infection was classified as per guidelines.

RESULTS

107 children [64 boys, age 97(18-168) months] were enrolled. 78(72.9%) had infection, 26(24%) had severe sepsis and 60(56%) had systemic inflammatory response syndrome. The commonest site of infection was ascitic fluid (n=37), followed by pneumonia (n=24), urinary tract (n=15), bacteraemia (n=10), cholangitis (n=8) and cellulitis (n=3). nCD64 (cut-off-51%, AUC-0.82) had a higher sensitivity (79.5%) and specificity (82.8%) than procalcitonin (cut-off ≥0.58ng/mL, AUC-0.74, sensitivity-76.9% and specificity-62.1%) for diagnosis of infection. nCD64 and procalcitonin correlated with infection severity, being highest in children with severe sepsis [88(71-97) %and 1.98(0.83-10.36) ng/mL], than in infection alone [72(45-84) % and 1.09(0.45-2.07) ng/mL], and no-infection [36(20.2-48) % and 0.42(0.19-1.08) ng/mL]. There was no difference in diagnostic utility of procalcitonin or nCD64 with different sites of infection. Elevation of all 3 parameters (nCD64, PCT and total leukocyte count) was uncommon but highly specific for presence of infection.

CONCLUSION

nCD64 identifies infection better than procalcitonin and correlates well with infection severity in children with DCLD.

Benefits and Harms of Procalcitonin- or C-Reactive Protein-Guided Antimicrobial Discontinuation in Critically Ill Adults With Sepsis: A Systematic Review and Network Meta-Analysis

OBJECTIVES

In sepsis treatment, antibiotics are crucial, but overuse risks development of antibiotic resistance. Recent guidelines recommended the use of procalcitonin to guide antibiotic cessation, but solid evidence is insufficient. Recently, concerns were raised that this strategy would increase recurrence. Additionally, optimal protocol or difference from the commonly used C-reactive protein (CRP) are uncertain. We aimed to compare the effectiveness and safety of procalcitonin- or CRP-guided antibiotic cessation strategies with standard of care in sepsis.

DATA SOURCES

A systematic search of PubMed, Embase, CENTRAL, Igaku Chuo Zasshi, ClinicalTrials.gov , and World Health Organization International Clinical Trials Platform.

STUDY SELECTION

Randomized controlled trials involving adults with sepsis in intensive care.

DATA EXTRACTION

A systematic review with network meta-analyses was performed. The Grading of Recommendations, Assessments, Developments, and Evaluation method was used to assess certainty.

DATA SYNTHESIS

Eighteen studies involving 5023 participants were included. Procalcitonin-guided and CRP-guided strategies shortened antibiotic treatment (-1.89 days [95% CI, -2.30 to -1.47], -2.56 days [95% CI, -4.21 to -0.91]) with low- to moderate-certainty evidence. In procalcitonin-guided strategies, this benefit was consistent even in subsets with shorter baseline antimicrobial duration (7-10 d) or in Sepsis-3, and more pronounced in procalcitonin cutoff of "0.5 μg/L and 80% reduction." No benefit was observed when monitoring frequency was less than half of the initial 10 days. Procalcitonin-guided strategies lowered mortality (-27 per 1000 participants [95% CI, -45 to -7]) and this was pronounced in Sepsis-3, but CRP-guided strategies led to no difference in mortality. Recurrence did not increase significantly with either strategy (very low to low certainty).

CONCLUSIONS

In sepsis, procalcitonin- or CRP-guided antibiotic discontinuation strategies may be beneficial and safe. In particular, the usefulness of procalcitonin guidance for current Sepsis-3, where antimicrobials are used for more than 7 days, was supported. Well-designed studies are needed focusing on monitoring protocol and recurrence.

Th17/Treg balance: the bloom and wane in the pathophysiology of sepsis

Sepsis is a multi-organ dysfunction characterized by an unregulated host response to infection. It is associated with high morbidity, rapid disease progression, and high mortality. Current therapies mainly focus on symptomatic treatment, such as blood volume supplementation and antibiotic use, but their effectiveness is limited. Th17/Treg balance, based on its inflammatory property, plays a crucial role in determining the direction of the inflammatory response and the regression of organ damage in sepsis patients. This review provides a summary of the changes in T-helper (Th) 17 cell and regulatory T (Treg) cell differentiation and function during sepsis, the heterogeneity of Th17/Treg balance in the inflammatory response, and the relationship between Th17/Treg balance and organ damage. Th17/Treg balance exerts significant control over the bloom and wanes in host inflammatory response throughout sepsis.

Linezolid dose adjustment according to therapeutic drug monitoring helps reach the goal concentration in severe patients, and the oldest seniors benefit more

BACKGROUND

The elderly with severe infection increased dramatically in intensive care unit (ICU). Proper antimicrobial therapy help improve the prognosis. Linezolid, as an antimicrobial drug, is commonly utilized to treat patients infected with methicillin-resistant S. aureus and vancomycin-resistant enterococci. Clinical evidence suggests elderly patients prone to linezolid overexposure. Here, we describe the results of three years' linezolid adjustment experiences according to therapeutic drug monitoring (TDM), especially in the oldest old.

METHODS

Linezolid therapeutic drug monitoring data were collected between January 2020 and November 2022 from patients who were admitted to ICU and treated with linezolid. All the patients started with a dosage of 600 mg, twice daily. The first TMD was carried out ten minutes before the seventh administration. The dosage adjustment was determined by the doctor according to the first TMD and patients' condition, and the repeated TDM was conducted as required. The dosage adjustment in different age group was recorded. Laboratory data were compared between the old and the oldest old. The high mortality risk of the oldest old was also explored.

RESULTS

Data of 556 linezolid TDM from 330 patients were collected. Among which, 31.6%, 54.8%, and 75% of patients had supra-therapeutic linezolid trough concentrations at the first TDM assessment in different age group, leading to the dosage adjustment rate of 31.0%, 40.3%, 68.8% respectively. The linezolid dosage adjustments according to TDM help to reach therapeutic concentration. The oldest old was in high risk of linezolid overexposure with lowercreatinine clearance. The norepinephrine maximum dosage but not linezolid Cmin was associated with 28-day mortality in the oldest old.

CONCLUSIONS

Elderly patients with linezolid conventional 600 mg twice-daily dose might be at a high risk of overexposure, especially in the oldest old. The linezolid dosage adjustments according to TDM help reach the therapeutic concentration. The high mortality of the oldest old was not related with initial linezolid overexposure.

Pushing the boundaries of innovation: the potential of ex vivo organ perfusion from an interdisciplinary point of view

Ex vivo machine perfusion (EVMP) is an emerging technique for preserving explanted solid organs with primary application in allogeneic organ transplantation. EVMP has been established as an alternative to the standard of care static-cold preservation, allowing for prolonged preservation and real-time monitoring of organ quality while reducing/preventing ischemia-reperfusion injury. Moreover, it has paved the way to involve expanded criteria donors, e.g., after circulatory death, thus expanding the donor organ pool. Ongoing improvements in EVMP protocols, especially expanding the duration of preservation, paved the way for its broader application, in particular for reconditioning and modification of diseased organs and tumor and infection therapies and regenerative approaches. Moreover, implementing EVMP for in vivo-like preclinical studies improving disease modeling raises significant interest, while providing an ideal interface for bioengineering and genetic manipulation. These approaches can be applied not only in an allogeneic and xenogeneic transplant setting but also in an autologous setting, where patients can be on temporary organ support while the diseased organs are treated ex vivo, followed by reimplantation of the cured organ. This review provides a comprehensive overview of the differences and similarities in abdominal (kidney and liver) and thoracic (lung and heart) EVMP, focusing on the organ-specific components and preservation techniques, specifically on the composition of perfusion solutions and their supplements and perfusion temperatures and flow conditions. Novel treatment opportunities beyond organ transplantation and limitations of abdominal and thoracic EVMP are delineated to identify complementary interdisciplinary approaches for the application and development of this technique.

Predictive value of risk factors for prognosis of patients with sepsis in intensive care unit

Sepsis has emerged as a major global public health concern due to its elevated mortality and high cost of care. This study aimed to evaluate the risk factors associated with the mortality of sepsis patients in the Intensive Care Unit (ICU), and to intervene in the early stages of sepsis in order to improve patient outcomes and reduce mortality. From January 1st, 2021 to December 31st, 2021, Longhua Hospital Affiliated to Shanghai University of Traditional Chinese Medicine, Huashan Hospital Affiliated to Fudan University, and The Seventh People's Hospital Affiliated to Shanghai University of Traditional Chinese Medicine were designated as sentinel hospitals, and sepsis patients in their respective ICU and Emergency ICU were selected as research subjects, and divided into survivors and non-survivors according to their discharge outcomes. The mortality risk of sepsis patients was subsequently analyzed by logistic regression. A total of 176 patients with sepsis were included, of which 130 (73.9%) were survivors and 46 (26.1%) were non-survivors. Factors identified as having an impact on death among sepsis patients included female [Odds Ratio (OR) = 5.135, 95% confidence interval (CI): 1.709, 15.427, P = .004)], cardiovascular disease (OR = 6.272, 95% CI: 1.828, 21.518, P = .004), cerebrovascular disease (OR = 3.133, 95% CI: 1.093, 8.981, P = .034), pulmonary infections (OR = 6.700, 95% CI: 1.744, 25.748, P = .006), use of vasopressors (OR = 34.085, 95% CI: 10.452, 111.155, P < .001), WBC < 3.5 × 109/L (OR = 9.752, 95% CI: 1.386, 68.620, P = .022), ALT < 7 U/L (OR = 7.672, 95% CI: 1.263, 46.594, P = .027), ALT > 40 U/L (OR = 3.343, 95% CI: 1.097, 10.185, P = .034). Gender, cardiovascular disease, cerebrovascular disease, pulmonary infections, the use of vasopressors, WBC, and ALT are important factors in evaluating the prognostic outcome of sepsis patients in the ICU. This suggests that medical professionals should recognize them expeditiously and implement aggressive treatment tactics to diminish the mortality rate and improve outcomes.

Provision of Microbiology, Infection Services and Antimicrobial Stewardship in Intensive Care: A Survey across the Critical Care Networks in England and Wales

Infection rounds in Intensive Care Units (ICU) can impact antimicrobial stewardship (AMS). The aim of this survey was to assess the availability of microbiology, infection, AMS services, and antimicrobial prescribing practices in the UK ICUs. An online questionnaire was sent to clinical leads for ICUs in each region listed in the Critical Care Network for the UK. Out of 217 ICUs, 87 deduplicated responses from England and Wales were analyzed. Three-quarters of those who responded had a dedicated microbiologist, and 50% had a dedicated infection control prevention nurse. Infection rounds varied in their frequency, with 10% providing phone advice only. Antibiotic guidance was available in 99% of the units; only 8% of those were ICU-specific. There were variations in the availability of biomarkers & the duration of antibiotics prescribed for pneumonia (community, hospital, or ventilator), urinary, intra-abdominal, and line infections/sepsis. Antibiotic consumption data were not routinely discussed in a multi-disciplinary meeting. The electronic prescription was available in ~60% and local antibiotic surveillance data in only 47% of ICUs. The survey highlights variations in practice and AMS services and may offer the opportunity to further collaborations and share learnings to support the safe use of antimicrobials in the ICU.

Cervical insufficiency, amniotic fluid sludge, intra-amniotic infection, and maternal bacteremia: the need for a point-of-care test to assess inflammation and bacteria in amniotic fluid

Acute cervical insufficiency is frequently associated with subclinical intra-amniotic inflammation and intra-amniotic infection. Amniotic fluid analysis has been recommended prior to the placement of a cervical cerclage given that preexisting infection is associated with adverse pregnancy outcome. We report a case for which commonly available laboratory tests-amniotic fluid Gram stain, white blood cell count, and glucose concentration-did not detect either intra-amniotic inflammation, diagnosed by elevated amniotic fluid interleukin-6, or intra-amniotic infection, diagnosed by cultivation. Following cerclage placement, the patient developed clinical chorioamnionitis and bacteremia and experienced a spontaneous mid-trimester pregnancy loss. This case illustrates the need for a rapid and sensitive point-of-care test capable of detecting infection or inflammation, given recent evidence in support of treatment of intra-amniotic infection and intra-amniotic inflammation with antimicrobial agents.

Ceftazidime/Avibactam-Based Versus Polymyxin B-Based Therapeutic Regimens for the Treatment of Carbapenem-Resistant Klebsiella pneumoniae Infection in Critically Ill Patients: A Retrospective Cohort Study

INTRODUCTION

Considering the importance of ceftazidime/avibactam (CAZ/AVI) and polymyxin B (PMB) in treating carbapenem-resistant Klebsiella pneumoniae (CRKP) infection, it is essential to evaluate the efficacy and safety of these agents and provide appropriate medical advice to clinical specialists.

METHODS

We conducted a retrospective cohort study in two Chinese tertiary hospitals for critically ill patients with CRKP infection who received at least 24-h CAZ/AVI-based or PMB-based treatment. A binary logistic model and a Cox proportional hazards regression model were constructed to analyze variables that could potentially affect 30-day microbiological eradication and all-cause mortality, respectively.

RESULTS

From January 2019 to December 2021, 164 eligible patients were divided into CAZ/AVI and PMB cohorts. A notably lower 30-day mortality rate (35.4% vs 69.5%, P < 0.001) and a higher 30-day microbiological eradication rate (80.5% vs 32.9%, P < 0.001) were observed for patients receiving CAZ/AVI-based treatment, compared with cases in the PMB group. A longer antimicrobial treatment duration (> 7 days) could also significantly decrease the mortality rate and increase the microbiological eradication rate. Female patients had a higher survival rate than male patients. Age over 65 years, sepsis, continuous renal replacement therapy, and organ transplantation were identified as negative factors for survival. In the subgroup analysis, CAZ/AVI combined with tigecycline or amikacin could effectively lower mortality. According to safety evaluation results, potential elevation of hepatic enzymes was associated with CAZ/AVI-based treatment, while renal impairment was probably related to PMB-based treatment.

CONCLUSIONS

CAZ/AVI was more effective than PMB in treating CRKP-infected patients. Tigecycline and amikacin were proven to be beneficial as concomitant agents in combination with CAZ/AVI. A treatment period lasting over 7 days was recommended. Hepatoxicity of CAZ/AVI and nephrotoxicity of PMB should be monitored carefully. Further well-designed studies should be performed to verify our conclusion.

Antimicrobial Stewardship for the Infusion Nurse

The consequences of antimicrobial overuse are complex. Censoring overuse requires strategic efforts directed at tailoring antimicrobial prescribing habits. Antimicrobial stewardship combats the negative consequences for patients and society. All members of the health care team can influence stewardship efforts in the patient treated for infectious diseases. Many of the potent antimicrobials used today are given by infusion, providing an exceptional opportunity for the infusion nurse to become a crucial part of the antimicrobial stewardship team. The goal of this article is to explain why antimicrobials are worth caring for and preserving, as well as to define the role of the infusion nurse in the antimicrobial stewardship team.

Modulating the evolutionary trajectory of tolerance using antibiotics with different metabolic dependencies

Antibiotic tolerance, or the ability of bacteria to survive antibiotic treatment in the absence of genetic resistance, has been linked to chronic and recurrent infections. Tolerant cells are often characterized by a low metabolic state, against which most clinically used antibiotics are ineffective. Here, we show that tolerance readily evolves against antibiotics that are strongly dependent on bacterial metabolism, but does not arise against antibiotics whose efficacy is only minimally affected by metabolic state. We identify a mechanism of tolerance evolution in E. coli involving deletion of the sodium-proton antiporter gene nhaA, which results in downregulated metabolism and upregulated stress responses. Additionally, we find that cycling of antibiotics with different metabolic dependencies interrupts evolution of tolerance in vitro, increasing the lifetime of treatment efficacy. Our work highlights the potential for limiting the occurrence and extent of tolerance by accounting for antibiotic dependencies on bacterial metabolism.

On prioritising global health's triple crisis of sepsis, COVID-19 and antimicrobial resistance: a mixed-methods study from Malawi

Sepsis causes 20% of global deaths, particularly among children and vulnerable populations living in developing countries. This study investigated how sepsis is prioritised in Malawi’s health system to inform health policy. In this mixed-methods study, twenty multisectoral stakeholders were qualitatively interviewed and asked to quantitatively rate the likelihood of sepsis-related medium-term policy outcomes being realised. Respondents indicated that sepsis is not prioritised in Malawi due to a lack of local sepsis-related evidence and policies. However, they highlighted strong linkages between sepsis and maternal health, antimicrobial resistance and COVID-19, which are already existing national priorities, and offers opportunities for sepsis researchers as policy entrepreneurs. To address the burden of sepsis, we recommend that funding should be channelled to the generation of local evidence, evidence uptake, procurement of resources and treatment of sepsis cases, development of appropriate indicators for sepsis, adherence to infection prevention and control measures, and antimicrobial stewardship.

Practice Summary of Antimicrobial Therapy for Commonly Encountered Conditions in the Neonatal Intensive Care Unit: A Canadian Perspective

Neonates are highly susceptible to infections owing to their immature cellular and humoral immune functions, as well the need for invasive devices. There is a wide practice variation in the choice and duration of antimicrobial treatment, even for relatively common conditions in the NICU, attributed to the lack of evidence-based guidelines. Early decisive treatment with broad-spectrum antimicrobials is the preferred clinical choice for treating sick infants with possible bacterial infection. Prolonged antimicrobial exposure among infants without clear indications has been associated with adverse neonatal outcomes and increased drug resistance. Herein, we review and summarize the best practices from the existing literature regarding antimicrobial use in commonly encountered conditions in neonates.

Short- versus prolonged-course antibiotic therapy for sepsis or infectious diseases in critically ill adults: a systematic review and meta-analysis

BACKGROUND

The 2016 International Guidelines for the Management of Sepsis and Septic Shock recommend antibiotic therapy for 7-10 days for most patients with sepsis. However, evidence on critically ill patients is limited. Thus, we conducted the first systematic review and meta-analysis comparing the effectiveness and adverse events of shorter- (≤1 week) with longer-course antibiotics in adults with critical infections including sepsis.

METHODS

We searched the MEDLINE, Cochrane Central Register of Controlled Trials, and Igaku Chuo Zasshi databases for randomised controlled trials (RCTs) and observational studies (OSs) from inception to 31 March 2021.

RESULTS

We included 6 of 3,766 identified articles, incorporating data from 4 RCTs and 2 OSs (1,721 patients) in meta-analyses. Three RCTs and one OS focussed on ventilator-associated pneumonia, and one RCT and one OS investigated intra-abdominal infections. The severity score levels were similar to that of sepsis, but no study comprehensively focussing on sepsis was found. There were no significant differences in mortality at a maximum follow-up of 30 days (RR 1.08, 95%CI 0.80-1.46); 28-day mortality, clinical cure, the occurrence of new events, and the emergence of resistant organisms between the groups in the RCTs. The OSs findings were consistent. The quality of evidence was assessed as very low to moderate using the GRADE approach, with no uniform description of severity scores, sepsis, or adverse events.

CONCLUSIONS

Shorter, fixed-duration antibiotic therapy for clinically heterogeneous sepsis or severe infections was not associated with poorer outcomes, but the overall quality of evidence was poor.

Efficacy and appropriateness of novel antibiotics in response to antimicrobial-resistant Gram-negative bacteria in patients with sepsis in the ICU

INTRODUCTION

There is an ever-increasing range of antibiotic-resistant pathogens that have led to higher community-acquired infections, and substantial mortality rates in critically ill patients.

AREAS COVERED

We have critically appraised available evidence through a structured literature review, investigating effective empiric antibiotic administration and appropriateness on outcomes of critically ill patients with an increased risk of developing resistant pathogens. The use of new antibiotics should be determined based on relevant knowledge of their spectrum and properties to provide effective mode of action for critically ill patients.

EXPERT OPINION

Restricting severely ill patients access to new broad-spectrum empirical drugs is not the answer. Rather there should be a focus on identifying host response to infection to differentiate between colonization or contamination and true infection, and the sensitivity to antibiotics used in the intensive care unit (ICU).

Management relies on adequate antibiotic administration, the ability to monitor response, and facilitate the cessation of antibiotic treatment. The major determinant of patient success in a patient with a severe infection is the 'right' antibiotic or complementary course of treatment. As an overarching criterion, the following 3 appropriate "Ds" should be considered: Dosing, Duration and De-escalation to empirically assess the right antibiotic optimal antimicrobial selection.

Do we overtreat patients with presumed neutropenic sepsis?

PURPOSE

Many aspects of the management of neutropenic sepsis remain controversial. These include the choice of empiric antibiotic, the duration of antibiotic therapy and the possibility that very low-risk cases may be managed safely with oral rather than intravenous therapy.

STUDY DESIGN

Retrospective cohort study conducted in a district general hospital serving a population of 148 000 in south west Scotland.

RESULTS

Fifty one patients with cancer, whose neutrophil count was less than 1.0×10⁹/L within 21 days of their last chemotherapy, were admitted as a medical emergency in 2019. All received antibiotic because of presumed neutropenic sepsis. A total of 4 patients had positive blood cultures (group 1), 12 patients had a clinical focus of infection but no clear pathogen (group 2), while 35 patients had neither (group 3). Group 3 patients were more likely to have a solid tumour, less likely to be febrile, had shorter time to neutrophil recovery and higher Multinational Association of Supportive Care in Cancer scores, though not all of these comparisons achieved statistical significance. Median intravenous plus oral antibiotic duration in group 3 patients was 9 days with median hospital stay of 7 days, raising the possibility of overtreatment. Retrospectively, 23 (66%) group 3 patients had MASSC Risk Index greater than 21 suggesting they were at low risk of complications.

CONCLUSIONS

It seems likely that many low-risk neutropenic cancer patients with solid tumours could be managed as effectively and as safely with shorter courses of antibiotic, with oral rather than intravenous antibiotic, as outpatients rather than inpatients and with an overall positive impact on antimicrobial stewardship.

Advancing Diagnostic Stewardship for Healthcare Associated Infections, Antibiotic Resistance, and Sepsis

Diagnostic stewardship means ordering the right tests, for the right patient at the right time to inform optimal clinical care. Diagnostic stewardship is an integral part of antibiotic stewardship efforts to optimize antibiotic use and improve patient outcomes, including reductions in antibiotic resistance, and treatment of sepsis. CDC's Division of Healthcare Quality Promotion (DHQP) hosted a meeting on improving patient safety through diagnostic stewardship with a focus on the use of the laboratory. The meeting identified emerging issues in the field of diagnostic stewardship, raised awareness of these issues among stakeholders, and discussed strategies and interventions to address the issues-all with an emphasis on improved outcomes and patient safety. This white paper summarizes the key takeaways of the meeting including needs for diagnostic stewardship implementation, promising future avenues for diagnostic stewardship implementation, and areas of needed research.

Cytosolic DNA-STING-NLRP3 axis is involved in murine acute lung injury induced by lipopolysaccharide

The role of NOD-like receptor protein 3 (NLRP3)-mediated pyroptosis in acute lung injury (ALI) has been well identified previously. Stimulator of interferon genes (STING) is an indispensable adaptor protein, which could regulate inflammation and pyroptosis during infection; however, its role in lipopolysaccharide (LPS)-induced ALI remains obscure. This study aimed to explore whether STING participated in the development of LPS-induced ALI as well as the underlying mechanism. We confirmed that LPS significantly enhanced the expression and phosphorylation of STING in lung tissue and primary macrophages from mice. STING deficiency relieved inflammation and oxidative stress in LPS-treated murine lungs and macrophages. Meanwhile, STING deficiency also abolished the activation of NLRP3 inflammasome and pyroptosis; however, NLRP3 overexpression by adenovirus offset the beneficial effects of STING deficiency in macrophages treated with LPS. Additionally, the level of mitochondrial DNA (mt-DNA) significantly increased in macrophages after LPS treatment. Intriguingly, although exogenous mt-DNA stimulation did not influence the level of STING, it could still trigger the phosphorylation of STING as well as pyroptosis, inflammation, and oxidative stress of macrophages. And the adverse effects induced by mt-DNA could be offset after STING was knocked out. Furthermore, the inhibition of the sensory receptor of cytosolic DNA (cyclic GMP-AMP synthase, cGAS) also blocked the activation of STING and NLRP3 inflammasome, meanwhile, it alleviated ALI without affecting the expression of STING after LPS challenge. Furthermore, cGAS inhibition also blocked the production of cGAMP induced by LPS, indicating that mt-DNA and cGAS could activate STING-NLRP3-mediated pyroptosis independent of the expression of STING. Finally, we found that LPS upregulated the expression of transcription factor c-Myc, which subsequently enhanced the activity of STING promoter and promoted its expression without affecting its phosphorylation. Collectively, our study disclosed that LPS could activate STING in a cytosolic DNA-dependent manner and upregulate the expression of STING in a c-Myc-dependent manner, which cooperatively contribute to ALI.

Some Suggestions from PK/PD Principles to Contain Resistance in the Clinical Setting-Focus on ICU Patients and Gram-Negative Strains

The containment of the phenomenon of resistance towards antimicrobials is a priority, especially in preserving molecules acting against Gram-negative pathogens, which represent the isolates more frequently found in the fragile population of patients admitted to Intensive Care Units. Antimicrobial therapy aims to prevent resistance through several actions, which are collectively known as "antimicrobial stewardship", to be taken together, including the application of pharmacokinetic/pharmacodynamic (PK/PD) principles. PK/PD application has been shown to prevent the emergence of resistance in numerous experimental studies, although a straight translation to the clinical setting is not possible. Individualized antibiotic dosing and duration should be pursued in all patients, and even more especially when treating intensive care unit (ICU) septic patients in whom optimal exposure is both difficult to achieve and necessary. In this review, we report on the available data that support the application of PK/PD parameters to contain the development of resistance and we give some practical suggestions that can help to translate the benefit of PK/PD application to the bedside.