The intensive care medicine research agenda on multidrug-resistant bacteria, antibiotics, and stewardship

Inflammaging in Multidrug-Resistant Sepsis of Geriatric ICU Patients and Healthcare Challenges

Multidrug-resistant sepsis (MDR) is a pressing concern in intensive care unit (ICU) settings, specifically among geriatric patients who experience age-related immune system changes and comorbidities. The aim of this review is to explore the clinical impact of MDR sepsis in geriatric ICU patients and shed light on healthcare challenges associated with its management. We conducted a comprehensive literature search using the National Center for Biotechnology Information (NCBI) and Google Scholar search engines. Our search incorporated keywords such as "multidrug-resistant sepsis" OR "MDR sepsis", "geriatric ICU patients" OR "elderly ICU patients", and "complications", "healthcare burdens", "diagnostic challenges", and "healthcare challenges" associated with MDR sepsis in "ICU patients" and "geriatric/elderly ICU patients". This review explores the specific risk factors contributing to MDR sepsis, the complexities of diagnostic challenges, and the healthcare burden faced by elderly ICU patients. Notably, the elderly population bears a higher burden of MDR sepsis (57.5%), influenced by various factors, including comorbidities, immunosuppression, age-related immune changes, and resource-limited ICU settings. Furthermore, sepsis imposes a significant economic burden on healthcare systems, with annual costs exceeding $27 billion in the USA. These findings underscore the urgency of addressing MDR sepsis in geriatric ICU patients and the need for tailored interventions to improve outcomes and reduce healthcare costs.

Role of multidrug-resistant bacteria in weaning from invasive mechanical ventilation

BACKGROUND

Although multidrug-resistant bacteria (MDR) are common in patients undergoing prolonged weaning, there is little data on their impact on weaning and patient outcomes.

METHODS

This is a retrospective analysis of consecutive patients who underwent prolonged weaning and were at a university weaning centre from January 2018 to December 2020. The influence of MDR colonisation and infection on weaning success (category 3a and 3b), successful prolonged weaning from invasive mechanical ventilation (IMV) with or without the need for non-invasive ventilation (NIV) compared with category 3c (weaning failure 3cI or death 3cII) was investigated. The pathogen groups considered were: multidrug-resistant gram-negative bacteria (MDRGN), methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus spp. (VRE).

RESULTS

A total of 206 patients were studied, of whom 91 (44.2%) showed evidence of MDR bacteria (32% VRE, 1.5% MRSA and 16% MDRGN), with 25 patients also meeting the criteria for MDR infection. 70.9% of the 206 patients were successfully weaned from IMV, 8.7% died. In 72.2% of cases, nosocomial pneumonia and other infections were the main cause of death. Patients with evidence of MDR (infection and colonisation) had a higher incidence of weaning failure than those without evidence of MDR (48% vs. 34.8% vs. 21.7%). In multivariate analyses, MDR infection (OR 4.9, p = 0.004) was an independent risk factor for weaning failure, along with male sex (OR 2.3, p = 0.025), Charlson Comorbidity Index (OR 1.2, p = 0.027), pH (OR 2.7, p < 0.001) and duration of IMV before admission (OR 1.01, p < 0.001). In addition, MDR infection was the only independent risk factor for death (category 3cII), (OR 6.66, p = 0.007).

CONCLUSION

Patients with MDR infection are significantly more likely to die during the weaning process. There is an urgent need to develop non-antibiotic approaches for the prevention and treatment of MDR infections as well as clinical research on antibiotic stewardship in prolonged weaning as well as in ICUs.

Decision-making regarding antibiotic therapy duration: An observational study of multidisciplinary meetings in the intensive care unit

PURPOSE

Antibiotic therapy is commonly prescribed longer than recommended in intensive care patients (ICU). We aimed to provide insight into the decision-making process on antibiotic therapy duration in the ICU.

METHODS

A qualitative study was conducted, involving direct observations of antibiotic decision-making during multidisciplinary meetings in four Dutch ICUs. The study used an observation guide, audio recordings, and detailed field notes to gather information about the discussions on antibiotic therapy duration. We described the participants' roles in the decision-making process and focused on arguments contributing to decision-making.

RESULTS

We observed 121 discussions on antibiotic therapy duration in sixty multidisciplinary meetings. 24.8% of discussions led to a decision to stop antibiotics immediately. In 37.2%, a prospective stop date was determined. Arguments for decisions were most often brought forward by intensivists (35.5%) and clinical microbiologists (22.3%). In 28.9% of discussions, multiple healthcare professionals participated equally in the decision. We identified 13 main argument categories. While intensivists mostly used arguments based on clinical status, clinical microbiologists used diagnostic results in the discussion.

CONCLUSIONS

Multidisciplinary decision-making regarding the duration of antibiotic therapy is a complex but valuable process, involving different healthcare professionals, using a variety of argument-types to determine the duration of antibiotic therapy. To optimize the decision-making process, structured discussions, involvement of relevant specialties, and clear communication and documentation of the antibiotic plan are recommended.

NIR-activated quercetin-based nanogels embedded with CuS nanoclusters for the treatment of drug-resistant biofilms and accelerated chronic wound healing

We have developed multifunctional nanogels with antimicrobial, antioxidant, and anti-inflammatory properties, facilitating rapid wound healing. To prepare the multifunctional nanogels, we utilized quercetin (Qu) and a mild carbonization process to form carbonized nanogels (CNGs). These CNGs possess excellent antioxidative and bacterial targeting properties. Subsequently, we utilized the Qu-CNGs as templates to prepare nanogels incorporating copper sulfide (CuS) nanoclusters, further enhancing their functionality. Notably, the CuS/Qu-CNGs nanocomposites demonstrated an exceptional minimum inhibitory concentration against tested bacteria, approximately 125-fold lower than monomeric Qu or Qu-CNGs. This enhanced antimicrobial effect was achieved by leveraging near-infrared II (NIR-II) light irradiation. Additionally, the CuS/Qu-CNGs exhibited efficient penetration into the extracellular biofilm matrix, eradicating methicillin-resistant Staphylococcus aureus-associated biofilms in diabetic mice wounds. Furthermore, the nanocomposites were found to suppress proinflammatory cytokines, such as IL-1β, at the wound sites while regulating the expression of anti-inflammatory factors, including IL-10 and TGF-β1, throughout the recovery process. The presence of CuS/Qu-CNGs promoted angiogenesis, epithelialization, and collagen synthesis, thereby accelerating wound healing. Our developed CuS/Qu-CNGs nanocomposites have great potential in addressing the challenges associated with delayed wound healing caused by microbial pathogenesis.

A deep learning model for predicting multidrug-resistant organism infection in critically ill patients

BACKGROUND

This study aimed to apply the backpropagation neural network (BPNN) to develop a model for predicting multidrug-resistant organism (MDRO) infection in critically ill patients.

METHODS

This study collected patient information admitted to the intensive care unit (ICU) of the Affiliated Hospital of Qingdao University from August 2021 to January 2022. All patients enrolled were divided randomly into a training set (80%) and a test set (20%). The least absolute shrinkage and selection operator and stepwise regression analysis were used to determine the independent risk factors for MDRO infection. A BPNN model was constructed based on these factors. Then, we externally validated this model in patients from May 2022 to July 2022 over the same center. The model performance was evaluated by the calibration curve, the area under the curve (AUC), sensitivity, specificity, and accuracy.

RESULTS

In the primary cohort, 688 patients were enrolled, including 109 (15.84%) MDRO infection patients. Risk factors for MDRO infection, as determined by the primary cohort, included length of hospitalization, length of ICU stay, long-term bed rest, antibiotics use before ICU, acute physiology and chronic health evaluation II, invasive operation before ICU, quantity of antibiotics, chronic lung disease, and hypoproteinemia. There were 238 patients in the validation set, including 31 (13.03%) MDRO infection patients. This BPNN model yielded good calibration. The AUC of the training set, the test set and the validation set were 0.889 (95% CI 0.852-0.925), 0.919 (95% CI 0.856-0.983), and 0.811 (95% CI 0.731-0.891), respectively.

CONCLUSIONS

This study confirmed nine independent risk factors for MDRO infection. The BPNN model performed well and was potentially used to predict MDRO infection in ICU patients.

Antibacterial and phytochemical analysis of traditional medicinal plants: An alternative therapeutic Approach to conventional antibiotics

The purpose of this study was to carry out antibacterial and phytochemical analyses on six selected medicinal plants that have been traditionally used by the local people to treat and control different diseases. The antibacterial activities of methanolic extracts of these plants were assessed using the Agar well diffusion and Microtiter broth dilution methods. The root extract of Andrachne aspera showed significantly (p < 0.05) highest mean zone of inhibition at concentrations of 100 mg/ml (33 ± 0.17) and 200 mg/ml (33.5 ± 0.84) against S. epidermidis. The second highest mean zone of inhibition (24.8 ± 0.41) was recorded by Dichrostachys cinerea leaf extract against S. epidermidis at 200 mg/ml concentration. The minimum inhibitory concentrations 1.0 ± 0.0 was recorded by Andrachne aspera against E. faecalis and 2.0 ± 0.0 against S. aureus by Dichrostachys cinerea. The preliminary phytochemical analysis showed that Andrachne aspera and Dichrostachys cinerea contained strong concentration of Polyphenols and Flavonoids. Therefore, these two medicinal plant species have promising potential for further detailed investigations, including safety tests, characterization and isolation of bioactive secondary metabolites for the development of alternative drugs.

Extended Versus Intermittent Meropenem Infusion in the Treatment of Nosocomial Pneumonia: A Retrospective Single-Center Study

The efficacy of extended meropenem infusions in patients with nosocomial pneumonia is not well defined. Therefore, we compared the clinical outcomes of extended versus intermittent meropenem infusions in the treatment of nosocomial pneumonia. We performed a retrospective analysis of extended versus intermittent meropenem infusions in adult patients who had been treated for nosocomial pneumonia at a medical ICU between 1 May 2018 and 30 April 2020. The primary outcome was mortality at 14 days. Overall, 64 patients who underwent an extended infusion and 97 with an intermittent infusion were included in this study. At 14 days, 10 (15.6%) patients in the extended group and 22 (22.7%) in the intermittent group had died (adjusted hazard ratio (HR), 0.55; 95% confidence interval (CI): 0.23-1.31; p = 0.174). In the subgroup analysis, significant differences in mortality at day 14 were observed in patients following empirical treatment with meropenem (adjusted HR, 0.17; 95% CI: 0.03-0.96; p = 0.045) and in Gram-negative pathogens identified by blood or sputum cultures (adjusted HR, 0.01; 95% CI: 0.01-0.83; p = 0.033). Extended infusion of meropenem compared with intermittent infusion as a treatment option for nosocomial pneumonia may have a potential advantage in specific populations.

Risk predict model using multi-drug resistant organism infection from Neuro-ICU patients: a retrospective cohort study

The aim of this study was to analyze the current situation and risk factors of multi-drug-resistant organism (MDRO) infection in Neuro-intensive care unit (ICU) patients, and to develop the risk predict model. The data was collected from the patients discharged from Neuro-ICU of grade-A tertiary hospital at Guizhou province from January 2018 to April 2020. Binary Logistics regression was used to analyze the data. The model was examined by receiver operating characteristic curve (ROC). The grouped data was used to verify the sensitivity and specificity of the model. A total of 297 patients were included, 131 patients infected with MDRO. The infection rate was 44.11%. The results of binary Logistics regression showed that tracheal intubation, artery blood pressure monitoring, fever, antibiotics, pneumonia were independent risk factors for MDRO infection in Neuro-ICU (P < 0.05), AUC = 0.887. The sensitivity and specificity of ROC curve was 86.3% and 76.9%. The risk prediction model had a good predictive effect on the risk of MDRO infection in Neuro ICU, which can evaluate the risk and provide reference for preventive treatment and nursing intervention.

Risk of multi-drug-resistant organism acquisition from prior bed occupants in the intensive care unit: a meta-analysis

Multi-drug-resistant organisms (MDROs) have become a global threat to human health. Prior bed occupancy with MDRO infection/colonization is an exposure factor that is closely associated with the MDRO acquisition rates in subsequent bed patients in intensive care units (ICUs). A meta-analysis was conducted to investigate the risk of MDRO acquisition from prior bed occupants in the ICU. PubMed, Cochrane Library, Web of Science, and Embase databases and reference lists were searched for articles published up to December 2021. The Newcastle-Ottawa scale was used for quality assessment. The risk measure was calculated as the odds ratio (OR) and corresponding 95% confidence interval (CI), and the heterogeneity was tested using I2 method and Q test. Eight articles were analysed using a random-effects model. Of the 8147 patients exposed to prior bed occupants infected or colonized with MDROs, 421 had acquired MDROs. The control group consisted of 55,933 patients without exposure factors, of which 1768 had been infected/colonized with MDROs. The pooled acquisition OR for MDROs was 1.80 (95% CI: 1.42, 2.29), P<0.00001. Subgroup analysis based on multi-drug-resistant Gram-positive and Gram-negative organisms was conducted using a fixed-effects model. The results significantly varied between the groups. Heterogeneity was partially explained by the MDRO type. In conclusion, exposure of bed occupants to infected/colonized MDROs significantly increased the risk of MDRO acquisition in subsequent bed occupants.

Rapid Point-of-Care PCR Testing of Drug-Resistant Strains on Endotracheal Aspirate Samples: A Repurposed Effective Tool in the Stepwise Approach of Healthcare-Acquired Pneumonia-A Pilot Study

Healthcare-associated pneumonia (HCAP) is a common nosocomial infection with high morbidity and mortality. Culture-based detection of the etiologic agent and drug susceptibility is time-consuming, potentially leading to the inadequate use of broad-spectrum empirical antibiotic regimens. The aim was to evaluate the diagnostic capabilities of rapid point-of-care multiplex polymerase chain reaction (PCR) assays from the endotracheal aspirate of critically ill patients with HCAP. A consecutive series of 29 intensive care unit (ICU) patients with HCAP and a control group of 28 patients undergoing elective surgical procedures were enrolled in the study. The results of the PCR assays were compared to the culture-based gold standard. The overall accuracy of the PCR assays was 95.12%, with a sensitivity of 92.31% and a specificity of 97.67%. The median time was 90 min for the rapid PCR tests (p < 0.001), while for the first preliminary results of the cultures, it was 48 h (46-72). The overall accuracy for rapid PCR testing in suggesting an adequate antibiotic adjustment was 82.98% (95% CI 69.19-92.35%), with a specificity of 90% (95% CI 55.50-99.75%), a positive predictive value of 96.77% (95% CI 83.30-99.92%), and a negative predictive value of 56.25 (95% CII 29.88-80.25%). This method of rapid point-of-care PCR could effectively guide antimicrobial stewardship in patients with healthcare-acquired pneumonia.

Analysis on Bacterial Distribution and Change of Drug Resistance Rate in ICUs Across Southwest China from 2018 to 2022

Purpose

To analyze the distribution of bacteria and their drug resistance changes in Intensive Care Units (ICUs) across Southwest China from 2018 to 2022 and establish the antibiogram in this region to provide a basis for early empirical antimicrobial use.

Methods

Non-repetitive pathogens isolated from 109 member units with qualified data were obtained from the Antimicrobial Resistance Surveillance System in Sichuan Province, southwest China. The results obtained were interpreted with reference to CLSI M100-31th, and analyzed with WHONET 5.6 software.

Results

A total of 46,728 clinical isolates in ICUs were collected from 2018 to 2022, of which gram-negative organisms accounted for 76.1%, and gram-positive were 23.9%. The top 5 were Klebsiella pneumoniae, Acinetobacter baumannii, Escherichia coli, Pseudomonas aeruginosa and Staphylococcus aureus, respectively. From 2018 to 2022, the resistance rates of Klebsiella pneumoniae to imipenem and meropenem changed from 14.5% and 17.8% to 14.0% and 14.4%, showing a steady downward trend. Escherichia coli was always highly sensitive to carbapenems, with a total resistance rate of 3.8%. Among non-fermented gram-negative bacteria, the resistance rates of Pseudomonas aeruginosa to imipenem and meropenem decreased significantly, changed from 25.3% and 22.9% in 2018 to 20.0% and 15.1% in 2022. However, Acinetobacter baumannii showed high resistance rates of 76.2% and 76.9% to imipenem and meropenem, respectively. MRSA and MRCNS accounted for 31.7% and 82.7%, respectively. No vancomycin and linezolid-resistant Staphylococcus aureus was isolated. Enterococcus faecalis maintained high activity to vancomycin, teicoplanin, and linezolid; no vancomycin or teicoplanin-resistant Enterococcus faecium strains were detected.

Conclusion

From 2018 to 2022, the isolated bacteria in ICU were mainly gram-negative bacteria, and the growth of some multidrug-resistant bacteria was effectively controlled. All levels of medical institutions should continue to strengthen bacterial resistance surveillance, promote the establishment of antimicrobial stewardship program, and enhance restrictions on outpatient antimicrobial use.

Antibiotic stewardship in the ICU: time to shift into overdrive

Antibiotic resistance is a major health problem and will be probably one of the leading causes of deaths in the coming years. One of the most effective ways to fight against resistance is to decrease antibiotic consumption. Intensive care units (ICUs) are places where antibiotics are widely prescribed, and where multidrug-resistant pathogens are frequently encountered. However, ICU physicians may have opportunities to decrease antibiotics consumption and to apply antimicrobial stewardship programs. The main measures that may be implemented include refraining from immediate prescription of antibiotics when infection is suspected (except in patients with shock, where immediate administration of antibiotics is essential); limiting empiric broad-spectrum antibiotics (including anti-MRSA antibiotics) in patients without risk factors for multidrug-resistant pathogens; switching to monotherapy instead of combination therapy and narrowing spectrum when culture and susceptibility tests results are available; limiting the use of carbapenems to extended-spectrum beta-lactamase-producing Enterobacteriaceae, and new beta-lactams to difficult-to-treat pathogen (when these news beta-lactams are the only available option); and shortening the duration of antimicrobial treatment, the use of procalcitonin being one tool to attain this goal. Antimicrobial stewardship programs should combine these measures rather than applying a single one. ICUs and ICU physicians should be at the frontline for developing antimicrobial stewardship programs.

Cultures of antibiotic prescribing in medical intensive care

Antimicrobial resistance (AMR) continues to present a challenge to international healthcare systems and structures of public health. The focus on optimizing antibiotic prescribing in human populations has challenged healthcare systems charged with making responsible their physician-prescribers. In the United States, physicians in almost every specialty and role use antibiotics as part of their therapeutic armamentariums. In United States hospitals, most patients are administered antibiotics during their stay. Therefore, antibiotic prescribing and utilization is a commonly accepted part of medical practice. In this paper, we utilize social science work on antibiotic prescribing to examine a critical space of care in United States hospital settings. From March to August 2018, we used ethnographic methods to study hospital-based medical intensive care unit physicians at the offices and hospital floors they frequent in two urban United States teaching hospitals. We focused on eliciting the interactions and discussions surrounding antibiotic decision-making that are uniquely influenced by the context of medical intensive care units. We argue that antibiotic use in the medical intensive care units under study was shaped by urgency, hierarchy, and uncertainty representative of the medical intensive care unit's role within the larger hospital system. We conclude that by studying the culture of antibiotic prescribing in medical intensive care units, we can see more clearly both the vulnerability of the looming antimicrobial resistance crisis and by contrast the perceived insignificance of stewarding antibiotic use when considered alongside the fragility of life amidst acute medical concerns regularly experienced in the unit.

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.

Antibiotic Usage in the COVID-19 Intensive Care Unit of an Infectious Diseases Hospital from Nord-Eastern Romania

Background and Objectives. The intensive care unit (ICU), especially in an infectious disease hospital, is both an area with a high consumption of antibiotics (atb) and a "reservoir" of multidrug-resistant bacteria. We proposed the analysis of antibiotic therapy practices in such a department that treated, in conditions of a pandemic wave, patients with COVID-19 and its complications. Materials and Methods. This was a retrospective transversal study of 184 COVID-19 patients treated in the ICU of a regional infectious disease hospital of Iaşi, Romania, in a 3-month interval of 2020 and 2021. Results. All the included patients (Caucasians, 53% males, with a median age of 68 years, and a Charlton comorbidity index of 3) received at least one antibiotic during their stay in the ICU (43% also had antibiotics prior to hospital admission and 68% in the Infectious Diseases ward). Only 22.3% of the ICU patients had only one antibiotic. A total of 77.7% of them started with an association of two antibiotics, and 19.6% of them received more than three antibiotics. The most-used ones were linezolid (77.2%), imipenem (75.5%), and ceftriaxone (33.7%). The median atb duration was 9 days. No change in the number or type of atb prescription was seen in 2021 (compared to 2020). Only 9.8% of the patients had a microbiological confirmation of bacterial infection. A total of 38.3% of the tested patients had elevated procalcitonin levels at ICU admission. The overall fatality rate was 68.5%, with no significant differences between the two analyzed periods or the number of administered antibiotics. More than half (51.1%) of the patients developed oral candidiasis during their stay in the ICU, but only 5.4% had C. difficile colitis. Conclusion. Antibiotics were widely used in our ICU patients in the presence of a reduced microbiological confirmation of a bacterial co-infection, and were justified by other clinical or biological criteria.

The Use of Antibiotics and Antimicrobial Resistance in Veterinary Medicine, a Complex Phenomenon: A Narrative Review

As warned by Sir Alexander Fleming in his Nobel Prize address: “the use of antimicrobials can, and will, lead to resistance”. Antimicrobial resistance (AMR) has recently increased due to the overuse and misuse of antibiotics, and their use in animals (food-producing and companion) has also resulted in the selection and transmission of resistant bacteria. The epidemiology of resistance is complex, and factors other than the overall quantity of antibiotics consumed may influence it. Nowadays, AMR has a serious impact on society, both economically and in terms of healthcare. This narrative review aimed to provide a scenario of the state of the AMR phenomenon in veterinary medicine related to the use of antibiotics in different animal species; the impact that it can have on animals, as well as humans and the environment, was considered. Providing some particular instances, the authors tried to explain the vastness of the phenomenon of AMR in veterinary medicine due to many and diverse aspects that cannot always be controlled. The veterinarian is the main reference point here and has a high responsibility towards the human–animal–environment triad. Sharing such a burden with human medicine and cooperating together for the same purpose (fighting and containing AMR) represents an effective example of the application of the One Health approach.

Association of Multidrug Resistance Bacteria and Clinical Outcomes of Adult Patients with Sepsis in the Intensive Care Unit

Background: Multi-drug resistance organisms (MDRO) often cause increased morbidity, mortality, and length of stays (LOS). However, there is uncertainty whether the infection of MDRO increase the morbidity, mortality, and ICU-LOS. Objective: This study was performed to determine the prevalence of MDRO in the ICU, the site of infection, and the association of MDRO or site of infection with mortality. The secondary outcome was determined by ascertaining the association of MDRO or site of infection with ICU-LOS. Methods: A retrospective cohort study was performed with adult sepsis patients in the ICU. Univariate and multivariate (MVA) logistic regression with cox regression modeling were performed to compute the association of MDRO with ICU mortality. MVA modelling was performed for ICU-LOS predictors. Results: Out of 228 patients, the isolated MDRO was 97 (42.5%), of which 78% were Gram-negative bacteria. The mortality rate among those with MDRO was 85 (37.3%). The hospital acquired infection (HAI) was a significant predictor for ICU-LOS in univariate linear regression (R2 = 0.034, p = 0.005). In MVA linear regression, both Enterococcus faecalis infection and Acinetobacter baumannii (AC)-MDRO were predictors for ICU-LOS with (R2 = 0.478, p < 0.05). In the univariate cox regression, only the infection with AC-MDRO was a risk factor for ICU-mortality with [HR = 1.802 (95% CI: 1.2−2.706; p = 0.005)]. Conclusions: Identifying risk factors for MDRO addresses the appropriate administration of empirical antibiotics and allows to effectively control the source of infection, which would reduce mortality and ICU-LOS. The usage of broad-spectrum antibiotics should be limited to those with substantial risk factors for acquiring MDRO.

A Systematic Review of Antibiotic Resistance Trends and Treatment Options for Hospital-Acquired Multidrug-Resistant Infections

Antimicrobial resistance is a major public health challenge described by the World Health Organization as one of the top 10 public health challenges worldwide. Drug-resistant microbes contribute significantly to morbidity and mortality in the hospital, especially in the critical care unit. The primary etiology of increasing antibiotic resistance is inappropriate and excessive use of antibiotics. The alarming rise of drug-resistant microbes worldwide threatens to erode our ability to treat infections with our current armamentarium of antibiotics.

Unfortunately, the pace of development of new antibiotics by the pharmaceutical industry has not kept up with rising resistance to expand our options to treat microbial infections. The costs of antibiotic resistance include death and disability, extended hospital stays due to prolonged sickness, need for expensive therapies, rising healthcare expenditure, reduced productivity from time out of the workforce, and rising penury. This review sums up the common mechanisms, trends, and treatment options for hospital-acquired multidrug-resistant microbes.

Clinical prediction models for multidrug-resistant organism colonisation or infection in critically ill patients: a systematic review protocol

INTRODUCTION

Multidrug-resistant organisms (MDROs) are pathogenic bacteria that are the leading cause of hospital-acquired infection which is associated with high morbidity and mortality rates in intensive care units, increasing hospitalisation duration and cost. Predicting the risk of MDRO colonisation or infection for critically ill patients supports clinical decision-making. Several models predicting MDRO colonisation or infection have been developed; however, owing to different disease scenarios, bacterial species and few externally validated cohorts in different prediction models; the stability and applicability of these models for MDRO colonisation or infection in critically ill patients are controversial. In addition, there are currently no standardised risk scoring systems to predict MDRO colonisation or infection in critically ill patients. The aim of this systematic review is to summarise and assess models predicting MDRO colonisation or infection in critically ill patients and to compare their predictive performance.

METHODS AND ANALYSIS

We will perform a systematic search of PubMed, Cochrane Library, CINAHL, Embase, Web of science, China National Knowledge Infrastructure and Wanfang databases to identify all studies describing the development and/or external validation of models predicting MDRO colonisation or infection in critically ill patients. Two reviewers will independently extract and review the data using the Data Extraction for Systematic Reviews of Prediction Modelling Studies checklist; they will also assess the risk of bias using the Prediction Model Risk of Bias Assessment Tool. Quantitative data on model predictive performance will be synthesised in meta-analyses, as applicable.

ETHICS AND DISSEMINATION

Ethical permissions will not be required because all data will be extracted from published studies. We intend to publish our results in peer-reviewed scientific journals and to present them at international conferences on critical care.

PROSPERO REGISTRATION NUMBER

CRD42022274175.

Instant Gratification and Overtreating to Be Safe: Perceptions of U.S. Intensive Care Unit Pharmacists and Residents on Antimicrobial Stewardship

Antimicrobial stewardship programs have been associated with numerous impacts on medical practice including reductions in costs, antimicrobial resistance, and adverse events. While antimicrobial stewardship is now considered an essential element of medical practice, the understandings of the value of antimicrobial stewardship among medical practitioners vary. Additionally, non-physician practitioners are regularly left out of antimicrobial stewardship interventions targeting antimicrobial decision-making. Here, we contribute the perspective from resident physicians and specialists in pharmacy regarding their involvement in antimicrobial prescribing. Notably, our semi-structured interviews with 10 residents and pharmacy specialists described their limited autonomy in the clinical setting. However, the participants regularly worked alongside primary antimicrobial decision-makers and described feeling pressure to overtreat to be safe. The clear rationales and motivations associated with antimicrobial prescribing have a noticeable impact on physicians in training and non-physician practitioners, and as such, we argue that antimicrobial stewardship interventions targeting primary antimicrobial decision-makers are missing an opportunity to address the breadth of antimicrobial prescribing culture. By looking at the perspectives and rationales of physicians in training and non-physician practitioners, we can see evidence that the act of antimicrobial prescribing is impacted by individuals on all levels of the hierarchies present in medical practice.

Why We May Need Higher Doses of Beta-Lactam Antibiotics: Introducing the 'Maximum Tolerable Dose'

The surge in antimicrobial resistance and the limited availability of new antimicrobial drugs has fueled the interest in optimizing antibiotic dosing. An ideal dosing regimen leads to maximal bacterial cell kill, whilst minimizing the risk of toxicity or antimicrobial resistance. For beta-lactam antibiotics specifically, PK/PD-based considerations have led to the widespread adoption of prolonged infusion. The rationale behind prolonged infusion is increasing the percentage of time the beta-lactam antibiotic concentration remains above the minimal inhibitory concentration (%fT>MIC). The ultimate goal of prolonged infusion of beta-lactam antibiotics is to improve the outcome of infectious diseases. However, merely increasing target attainment (or the %fT>MIC) is unlikely to lead to improved clinical outcome for several reasons. First, the PK/PD index and target are dynamic entities. Changing the PK (as is the case if prolonged instead of intermittent infusion is used) will result in different PK/PD targets and even PK/PD indices necessary to obtain the same level of bacterial cell kill. Second, the minimal inhibitory concentration is not a good denominator to describe either the emergence of resistance or toxicity. Therefore, we believe a different approach to antibiotic dosing is necessary. In this perspective, we introduce the concept of the maximum tolerable dose (MTD). This MTD is the highest dose of an antimicrobial drug deemed safe for the patient. The goal of the MTD is to maximize bacterial cell kill and minimize the risk of antimicrobial resistance and toxicity. Unfortunately, data about what beta-lactam antibiotic levels are associated with toxicity and how beta-lactam antibiotic toxicity should be measured are limited. This perspective is, therefore, a plea to invest in research aimed at deciphering the dose−response relationship between beta-lactam antibiotic drug concentrations and toxicity. In this regard, we provide a theoretical approach of how increasing uremic toxin concentrations could be used as a quantifiable marker of beta-lactam antibiotic toxicity.

Epigenetic-Mediated Antimicrobial Resistance: Host versus Pathogen Epigenetic Alterations

Since the discovery of antibiotics, humans have been benefiting from them by decreasing the morbidity and mortality associated with bacterial infections. However, in the past few decades, misuse of antibiotics has led to the emergence of bacterial infections resistant to multiple drugs, a significant health concern. Bacteria exposed to inappropriate levels of antibiotics lead to several genetic changes, enabling them to survive in the host and become more resistant. Despite the understanding and targeting of genetic-based biochemical changes in the bacteria, the increasing levels of antibiotic resistance are not under control. Many reports hint at the role of epigenetic modifications in the bacterial genome and host epigenetic reprogramming due to interaction with resistant pathogens. Epigenetic changes, such as the DNA-methylation-based regulation of bacterial mutation rates or bacteria-induced histone modification in human epithelial cells, facilitate its long-term survival. In this review article, epigenetic changes leading to the development of antibiotic resistance in clinically relevant bacteria are discussed. Additionally, recent lines of evidence focusing on human host epigenetic changes due to the human–pathogen interactions are presented. As genetic mechanisms cannot explain the transient nature of antimicrobial resistance, we believe that epigenetics may provide new frontiers in antimicrobial discovery.

Quercetin Reduces Inflammation and Protects Gut Microbiota in Broilers

The aim of this study was to investigate the effects of quercetin on inflammatory response and intestinal microflora in broiler chicken jejuna. A total of 120 broiler chickens were allocated into 3 groups: saline-challenged broilers fed a basal diet (CTR group), lipopolysaccharide (LPS)-challenged broilers fed a basal diet (L group) and LPS-challenged broilers fed a basal diet supplemented with 200 mg/kg quercetin (LQ group). Our results showed that LPS significantly increased expression of tumor necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-8, interferon (IFN)-γ, toll-like receptor (TLR)-4, Bax, Caspase-3 and diamine oxidase activity (DAO), and decreased expression of zona occludens-1 (ZO-1), Occludin and Bcl-2 in the jejunum, while dietary quercetin prevented the adverse effects of LPS injection. LPS injection significantly decreased the number of Actinobacteria, Armatimonadetes and Fibrobacteriae at the phylum level when compared to the CTR group. Additionally, at genus level, compared with the CTR group, the abundance of Halomonas, Micromonospora, Nitriliruptor, Peptococcus, Rubellimicrobium, Rubrobacter and Slaclda in L group was significantly decreased, while dietary quercetin restored the numbers of these bacteria. In conclusion, our results demonstrated that dietary quercetin could alleviate inflammatory responses of broiler chickens accompanied by modulating jejunum microflora.

Pharmaceutical Pollution in Aquatic Environments: A Concise Review of Environmental Impacts and Bioremediation Systems

The presence of emerging contaminants in the environment, such as pharmaceuticals, is a growing global concern. The excessive use of medication globally, together with the recalcitrance of pharmaceuticals in traditional wastewater treatment systems, has caused these compounds to present a severe environmental problem. In recent years, the increase in their availability, access and use of drugs has caused concentrations in water bodies to rise substantially. Considered as emerging contaminants, pharmaceuticals represent a challenge in the field of environmental remediation; therefore, alternative add-on systems for traditional wastewater treatment plants are continuously being developed to mitigate their impact and reduce their effects on the environment and human health. In this review, we describe the current status and impact of pharmaceutical compounds as emerging contaminants, focusing on their presence in water bodies, and analyzing the development of bioremediation systems, especially mycoremediation, for the removal of these pharmaceutical compounds with a special focus on fungal technologies.

Treatment of ventilator-associated pneumonia due to carbapenem-resistant Gram-negative bacteria with novel agents: a contemporary, multidisciplinary ESGCIP perspective

INTRODUCTION

: In the past 15 years, treatment of VAP caused by carbapenem-resistant Gram-negative bacteria (CR-GNB) has represented an intricate challenge for clinicians.

AREAS COVERED

In this perspective article, we discuss the available clinical data about novel agents for the treatment of CR-GNB VAP, together with general PK/PD principles for the treatment of VAP, in the attempt to provide some suggestions for optimizing antimicrobial therapy of CR-GNB VAP in the daily clinical practice.

EXPERT OPINION

Recently, novel BL and BL/BLI combinations have become available that have shown potent in vitro activity against CR-GNB and have attracted much interest as novel, less toxic, and possibly more efficacious options for the treatment of CR-GNB VAP compared with previous standard of care. Besides randomized controlled trials, a good solution to enrich our knowledge on how to use these novel agents at best in the near future, while at the same time remaining adherent to current evidence-based guidelines, is to improve our collaboration to conduct larger multinational observational studies to collect sufficiently large populations treated in real life with those novel agents for which guidelines currently do not provide a recommendation (in favor or against) for certain causative organisms.

Bacterial Infections, Antimicrobial Resistance and Antibiotic Therapy

Bacterial infections have been, and are very likely to continue to be, among the most serious problems in medicine [...].

Interprofessional Collaboration between ICU Physicians, Staff Nurses, and Hospital Pharmacists Optimizes Antimicrobial Treatment and Improves Quality of Care and Economic Outcome

(1) Background: Antibiotic resistance is a worldwide health threat. The WHO published a global strategic plan in 2001 to contain antimicrobial resistance. In the following year, a workshop identified crucial barriers to the implementation of the strategy, e.g., underdeveloped health infrastructures and the scarcity of valid data as well as a lack of implementation of antibiotic stewardship (ABS) programs in medical curricula. Here, we show that interprofessional learning and education can contribute to the optimization of antibiotic use and preserving antibiotic effectiveness. We have initiated interprofessional rounds on a medical intensive care unit (MICU) with a focus on gastroenterology, hepatology, infectious diseases, endocrinology, and liver transplantation. We integrated ICU physicians, hospital pharmacists, nursing staff, and medical students as well as students of pharmacy to broaden the rather technical concept of ABS with an interprofessional approach to conceptualize awareness and behavioral change in antibiotic prescription and use. Methods: Clinical performance data and consumption figures for antibiotics were analyzed over a 10-year period from 2012 to 2021. The control period covered the years 2012–2014. The intervention period comprised the years 2015–2021, following the implementation of an interprofessional approach to ABS at a MICU of a German university hospital. Data from the hospital pharmacy, hospital administration, and hospital information system were included in the analyses. A specific electronic platform was developed for the optimization of documentation, interprofessional learning, education, and sustainability. The years 2020 and 2021 were analyzed independently due to the SARS-CoV-2 pandemic and the care of numerous COVID-19 patients at the MICU. Results: Implementation of an interprofessional ABS program resulted in the optimization of antibiotic management at the MICU. The suggestions of the hospital pharmacist for optimization can be divided into the following categories (i) indication for and selection of therapy (43.6%), (ii) optimization of dosing (27.6%), (iii) drug interactions (9.4%), (iv) side effects (4.1%), and (v) other pharmacokinetic, pharmacodynamic, and pharmacoeconomic topics (15.3%). These suggestions were discussed among the interprofessional team at the MICU; 86.1% were consequently implemented and the prescription of antibiotics was changed. In addition, further analysis of the intensive care German Diagnosis Related Groups (G-DRGs) showed that the case mix points increased significantly by 31.6% during the period under review. Accordingly, the severity of illness of the patients treated at the ICU as measured by the Simplified Acute Physiology Score (SAPS) II increased by 21.4% and the proportion of mechanically ventilated patients exceeded 50%. Antibiotic spending per case mix point was calculated. While spending was EUR 60.22 per case mix point in 2015, this was reduced by 42.9% to EUR 34.37 per case mix point by 2019, following the implementation of the interprofessional ABS program on the MICU. Through close interprofessional collaboration between physicians, hospital pharmacists, and staff nurses, the consumption of broad-spectrum antibiotics, e.g., carbapenems, was significantly reduced, thus improving patient care. In parallel, the case mix and case mix index increased. Thus, the responsible use of resources and high-performance medicine are not contradictory. In our view, close interprofessional and interdisciplinary collaboration between physicians, pharmacists, and nursing staff will be of outstanding importance in the future to prepare health care professionals for global health care to ensure that the effectiveness of our antibiotics is preserved.

Microbiology Assessments in Critically Ill Patients

The prevalence of suspected or proven infections in critically ill patients is high, with a substantial attributable risk to in-hospital mortality. Coordinated guidance and interventions to improve the appropriate microbiological assessment for diagnostic and therapeutic decisions are therefore pivotal. Conventional microbiology follows the paradigm of "best practice" of specimen selection and collection, governed by laboratory processing and standard operating procedures, and informed by the latest developments and trends. In this regard, the preanalytical phase of a microbiological diagnosis is crucial since inadequate sampling may result in the incorrect diagnosis and inappropriate management. In addition, the isolation and detection of contaminants interfere with multiple intensive care unit (ICU) processes, which confound the therapeutic approach to critically ill patients. To facilitate bedside enablement, the microbiology laboratory should provide expedited feedback, reporting, and interpretation of results. Compared with conventional microbiology, novel rapid and panel-based diagnostic strategies have the clear advantages of a rapid turnaround time, the detection of many microorganisms including antimicrobial resistant determinants and thus promise substantial improvements in health care. However, robust data on the clinical evaluation of rapid diagnostic tests in presumed sepsis, sepsis and shock are extremely limited and more rigorous intervention studies, focusing on direct benefits for critically ill patients, are pivotal before widespread adoption of their use through the continuum of ICU stay. Advocating the use of these diagnostics without firmly establishing which patients would benefit most, how to interpret the results, and how to treat according to the results obtained, could in fact be counterproductive with regards to diagnostic "best practice" and antimicrobial stewardship. Thus, for the present, they may supplement but not yet supplant conventional microbiological assessments.

Predominance of Acinetobacter spp., Harboring the blaIMP Gene, Contaminating the Hospital Environment in a Tertiary Hospital in Mwanza, Tanzania: A Cross-Sectional Laboratory-Based Study

Data on colonization and hospital contamination of carbapenem-resistant Gram-negative bacteria (CR-GNB) are limited in low- and middle-income countries. We designed this study to determine the prevalence and co-existence of carbapenemase genes among CR-GNB isolated from clinical, colonization, and hospital environmental samples at a tertiary hospital in Mwanza, Tanzania. The modified Hodge test (MHT), the combined disk test (CDT), and the double-disk synergy test (DDST) were used for the phenotypic detection of carbapenemases. A multiplex PCR assay was used to detect bla_IMP and bla_KPC, and a singleplex PCR assay was used to detect bla_OXA-48. Data were analyzed by STATA version 13.0. Overall, 68.8% (44/64) of the CR-GNB had at least one phenotype by phenotypic methods, whereby 60.9% (39/64) were both CDT and DDST positive and 31.3% (20/64) were MHT positive. A total of 23/64 (35.9%) had at least one of the genes tested with the predominance of bla_IMP (91.3%; 21/23). In addition, 47.7% (21/44) of the CR-GNB phenotypes had at least one gene. Around 47.8% (11/23) of the CR-GNB carried multiple genes encoding for carbapenem resistance, with the maximum co-existence of bla_IMP/bla_KPC/bla_OXA-48 (45.5%; 5/11). The majority of carbapenem-resistant genes were detected in Acinetobacter spp. (82.6%; 19/23) and isolated from bed swabs (69.6%; 16/23). Acinetobacter spp. carrying the bla_IMP gene predominantly contaminated the hospital environment. Therefore, we recommend routine decontamination of inanimate hospital surfaces, including patient beds.

Catalytic and photoresponsive BiZ/CuxS heterojunctions with surface vacancies for the treatment of multidrug-resistant clinical biofilm-associated infections

We report a one-pot facile synthesis of highly photoresponsive bovine serum albumin (BSA) templated bismuth-copper sulfide nanocomposites (BSA-BiZ/Cu_xS NCs, where BiZ represents in situ formed Bi₂S₃ and bismuth oxysulfides (BOS)). As-formed surface vacancies and BiZ/Cu_xS heterojunctions impart superior catalytic, photodynamic and photothermal properties. Upon near-infrared (NIR) irradiation, the BSA-BiZ/Cu_xS NCs exhibit broad-spectrum antibacterial activity, not only against standard multidrug-resistant (MDR) bacterial strains but also against clinically isolated MDR bacteria and their associated biofilms. The minimum inhibitory concentration of BSA-BiZ/Cu_xS NCs is 14-fold lower than that of BSA-Cu_xS NCs because their multiple heterojunctions and vacancies facilitated an amplified phototherapeutic response. As-prepared BSA-BiZ/Cu_xS NCs exhibited substantial biofilm inhibition (90%) and eradication (>75%) efficiency under NIR irradiation. Furthermore, MRSA-infected diabetic mice were immensely treated with BSA-BiZ/Cu_xS NCs coupled with NIR irradiation by destroying the mature biofilm on the wound site, which accelerated the wound healing process via collagen synthesis and epithelialization. We demonstrate that BSA-BiZ/Cu_xS NCs with superior antimicrobial activity and high biocompatibility hold great potential as an effective photosensitive agent for the treatment of biofilm-associated infections.

Implementing an Antimicrobial Stewardship Program in the Intensive Care Unit by Engaging Critical Care Nurses

The continuing rise in the incidence of multidrug-resistant organism infections has made combating this grave threat a national imperative. One of the most potent weapons in our arsenal against such organisms is the prudent use of antibiotics. Antimicrobial stewardship (AMS) programs aim to slow the development of antimicrobial resistance through judicious, monitored use of antibiotics. Traditionally, AMS programs have included pharmacists and physicians with training in AWS, infectious disease physicians, hospital leadership, microbiologists, and infection prevention professionals. Nurses are missing from AMS programs, especially intensive care nurses. Critical care nurses provide the majority of patient care to ICU patients and monitor the progress of the patient's condition. The ICU nurse is an obvious asset to the AMS programs. ICU nurses are well-educated autonomous professionals with a unique role in coordinating with the critical care team. Critical care nurses already perform numerous nursing tasks with AWS functions. This, together with their unique perspective makes them a valuable asset that has often been overlooked. Traditionally, perceived barriers have kept ICU nurses from joining AMS teams. By removing these barriers and engaging critical care nurses in the important work of AWS, we can strengthen our AMS team and achieve optimal outcomes for our patients.

Multidisciplinary approach to a septic COVID-19 patient undergoing veno-venous extracorporeal membrane oxygenation and receiving thoracic surgery

A multidisciplinary approach appears to be fundamental for the treatment of critically ill patients with COVID-19, improving clinical outcomes, even in the most severe cases. Such severe cases are advisable to be collegially discussed between intensivists, surgeons, infectious disease, and other physicians potentially involved.

Prediction of ventilator-associated pneumonia outcomes according to the early microbiological response: a retrospective observational study

Ventilator-associated pneumonia is a leading infectious cause of morbidity in critically ill patients; yet current guidelines offer no indications for follow-up cultures.We aimed to evaluate the role of follow-up cultures and microbiological response 3 days after diagnosing ventilator-associated pneumonia as predictors of short- and long-term outcomes.We performed a retrospective analysis of a cohort prospectively collected from 2004 to 2017. Ventilator-associated pneumonia was diagnosed based on clinical, radiographic, and microbiological criteria. For microbiological identification, a tracheobronchial aspirate was performed at diagnosis and repeated after 72 h. We defined three groups when comparing the two tracheobronchial aspirate results: persistence, superinfection, and eradication of causative pathogens.One-hundred-fifty-seven patients were enrolled in the study, among whom microbiological persistence, superinfection, and eradication was present in 67 (48%), 25 (16%), and 65 (41%), respectively, after 72hs. Those with superinfection had the highest mortalities in the intensive care unit (p=0.015) and at 90 days (p=0.036), while also having the fewest ventilation-free days (p=0.024). Multivariable analysis revealed shock at VAP diagnosis (odds ratios [OR] 3.43; 95% confidence interval [CI] 1.25 to 9.40), Staphylococcus aureus isolation at VAP diagnosis (OR 2.87; 95%CI 1.06 to 7.75), and hypothermia at VAP diagnosis (OR 0.67; 95%CI 0.48 to 0.95, per +1°C) to be associated with superinfection.Our retrospective analysis suggests that ventilator-associated pneumonia short-term and long-term outcomes may be associated with superinfection in follow-up cultures. Follow-up cultures may help guiding antibiotic therapy and its duration. Further prospective studies are necessary to verify our findings.

Molecular Characterization Identifies Upstream Presence of ISAba1 to OXA Carbapenemase Genes in Carbapenem-Resistant Acinetobacter baumannii Isolated from a Tertiary Care Hospital in Western Maharashtra

Background  Evaluating the expression pattern of oxacillinases (OXA) carbapenemases is essential to understand the prevalence and spread of carbapenem resistance Acinetobacter baumannii .

Objectives  The aim of the study is to evaluate the presence of OXA carbapenemase genes and IS Aba1 upstream to these genes in carbapenem-resistant A. baumannii clinical isolates.

Materials and Methods   A. baumannii isolated from clinical samples were phenotypically identified and antibiotics sensitivity was performed. Multiplex polymerase chain reaction (PCR) was used to detect OXA51-like gene, OXA carbapenemases genes (OXA-23-like, OXA-24-like, and OXA-58-like), and IS Aba1 in carbapenem-resistant isolates.

Results  Out of 55 Acinetobacter isolates, 54 were confirmed as A. baumannii by PCR. Bla_OXA-23 -like gene was observed in 51 isolates of A. baumannii and none of the isolates showed the presence of bla_OXA-24 -like and bla_OXA-58 -like genes. Presence of IS Aba1 upstream to OXA-23-like gene, OXA-51-like gene, and both OXA-51-like/OXA-23-like genes was observed in 51, 7, and 4 A. baumannii isolates, respectively.

Conclusion  The genetic pattern of carbapenem-resistant A. baumannii isolated in this study was unique, which should be factored for clinical protocols to manage infections caused by emerging resistant strains of A. baumannii .

Antimicrobial stewardship, therapeutic drug monitoring and infection management in the ICU: results from the international A- TEAMICU survey

BACKGROUND

Severe infections and multidrug-resistant pathogens are common in critically ill patients. Antimicrobial stewardship (AMS) and therapeutic drug monitoring (TDM) are contemporary tools to optimize the use of antimicrobials. The A-TEAMICU survey was initiated to gain contemporary insights into dissemination and structure of AMS programs and TDM practices in intensive care units.

METHODS

This study involved online survey of members of ESICM and six national professional intensive care societies.

RESULTS

Data of 812 respondents from mostly European high- and middle-income countries were available for analysis. 63% had AMS rounds available in their ICU, where 78% performed rounds weekly or more often. While 82% had local guidelines for treatment of infections, only 70% had cumulative antimicrobial susceptibility reports and 56% monitored the quantity of antimicrobials administered. A restriction of antimicrobials was reported by 62%. TDM of antimicrobial agents was used in 61% of ICUs, mostly glycopeptides (89%), aminoglycosides (77%), carbapenems (32%), penicillins (30%), azole antifungals (27%), cephalosporins (17%), and linezolid (16%). 76% of respondents used prolonged/continuous infusion of antimicrobials. The availability of an AMS had a significant association with the use of TDM.

CONCLUSIONS

Many respondents of the survey have AMS in their ICUs. TDM of antimicrobials and optimized administration of antibiotics are broadly used among respondents. The availability of antimicrobial susceptibility reports and a surveillance of antimicrobial use should be actively sought by intensivists where unavailable. Results of this survey may inform further research and educational activities.

Predictive Performance of Risk Factors for Multidrug-Resistant Pathogens in Nosocomial Pneumonia

Rationale: In 2017, the International European Respiratory Society/European Society of Intensive Care Medicine/European Society of Clinical Microbiology and Infectious Diseases/Latin American Thoracic Society (European) guidelines defined new risk factors for multidrug-resistant (MDR) pathogens in patients with nosocomial pneumonia.Objectives: To assess the predictive performance of these newly defined risk factors for MDR pathogens.Methods: We enrolled 507 adult patients with nosocomial pneumonia who were treated in six intensive care units at the Hospital Clinic of Barcelona in Spain. Of the 503 patients at high MDR pathogen and mortality risk, 275 (54%) had no septic shock and 228 (46%) had septic shock.Results: Admission to hospital settings with high rates of MDR pathogens (n = 421; 83%) and prior antibiotic use (n = 399; 79%) showed the highest prevalence in the overall population, with sensitivities of 92% and 85% and negative predictive values of 85% and 82%, respectively. However, low specificities and low positive predictive values were found. Previous respiratory MDR pathogen isolation was less common (n = 17; 3%) but presented a specificity and positive predictive value of 100%. The area under the receiver operating characteristic curve was less than 0.6 for all risk factors and combinations.Conclusions: The risk factors proposed by the European Respiratory Society/European Society of Intensive Care Medicine/European Society of Clinical Microbiology and Infectious Diseases/Latin American Thoracic Society showed low accuracy for predicting MDR pathogens in intensive care unit acquired pneumonia (ICU-AP). Admission to hospital settings with high rates of MDR pathogens and prior antibiotic use were the most prevalent risk factors, with a high sensitivity for predicting these microorganisms; prior positive cultures for MDR pathogens showed high specificity but very low sensitivity. Combinations of risk factors did not show any great accuracy for predicting these microorganisms. Further studies assessing combined strategies of risk stratification and complementary methods are now warranted.

Nosocomial Infection

OBJECTIVE

The first 70 years of critical care can be considered a period of "industrial revolution-like" advancement in terms of progressing the understanding and care of critical illness. Unfortunately, like the industrial revolution's impact on the environment, advancing ICU care of increasingly elderly, immunosuppressed, and debilitated individuals has resulted in a greater overall burden and complexity of nosocomial infections within modern ICUs. Given the rapid evolution of nosocomial infections, the authors provide an updated review.

DATA SOURCES AND STUDY SELECTION

We searched PubMed and OVID for peer-reviewed literature dealing with nosocomial infections in the critically ill, as well as the websites of government agencies involved with the reporting and prevention of nosocomial infections. Search terms included nosocomial infection, antibiotic resistance, microbiome, antibiotics, and intensive care.

DATA EXTRACTION AND DATA SYNTHESIS

Nosocomial infections in the ICU setting are evolving in multiple domains including etiologic pathogens plus novel or emerging pathogens, prevalence, host risk factors, antimicrobial resistance, interactions of the host microbiome with nosocomial infection occurrence, and understanding of pathogenesis and prevention strategies. Increasing virulence and antimicrobial resistance of nosocomial infections mandate increasing efforts toward their prevention.

CONCLUSIONS

Nosocomial infections are an important determinant of outcome for patients in the ICU setting. Systematic research aimed at improving the prevention and treatment of nosocomial infections is still needed.

Individual and collective impact of Klebsiella pneumoniae carbapenemase (KPC)-producing K. pneumoniae in patients admitted to the ICU

KPC-producing Klebsiella pneumoniae (KPC-Kp) raises major concerns in the context of intensive care, owing to limited treatment options and the ability to cause outbreaks in this specific setting. The objectives of this review are to give an overview of the burden of KPC-Kp in ICU patients and to discuss methodological issues and limitations regarding the quality of data available. Robust and reliable assessment of the KPC-Kp impact in the ICU should take into consideration not only characteristics of the individuals, but also of the health systems including length of stay, costs and hospital organization issues. Estimates of mortality reported in the current literature are weakened by the poor quality of adjustment for age-specific risks, co-morbidities, and appropriateness of therapy. All these confounding factors should be taken into account in models, with consideration of control groups and competing risks that is currently lacking in the published literature. Since development of antibiotic resistance is an unstoppable phenomenon and economic and human resources are facing progressive limitations due to budget constraints, cost-saving strategies targeted to avoid ICU closure, temporary limitation of admissions or delayed hospital discharge are necessary. The early identification of KPC-Kp-colonized patients through active screening strategies is likely to be the cornerstone of such a cost-saving strategy. However, there are still many open issues concerning which of these strategies are the most effective. Owing to extreme heterogeneity and several methodological flaws in current publications, future studies investigating the long-term sequelae and economic impact of KPC-Kp in the ICU are urgently needed.

Cytosine Base Editor-Mediated Multiplex Genome Editing to Accelerate Discovery of Novel Antibiotics in Bacillus subtilis and Paenibacillus polymyxa

Genome-based identification of new antibiotics is emerging as an alternative to traditional methods. However, uncovering hidden antibiotics under the background of known antibiotics remains a challenge. To over this problem using a quick and effective genetic approach, we developed a multiplex genome editing system using a cytosine base editor (CBE). The CBE system achieved simultaneous double, triple, quadruple, and quintuple gene editing with efficiencies of 100, 100, 83, and 75%, respectively, as well as the 100% editing efficiency of single targets in Bacillus subtilis. Whole-genome sequencing of the edited strains showed that they had an average of 8.5 off-target single-nucleotide variants at gRNA-independent positions. The CBE system was used to simultaneously knockout five known antibiotic biosynthetic gene clusters to leave only an uncharacterized polyketide biosynthetic gene cluster in Paenibacillus polymyxa E681. The polyketide showed antimicrobial activities against gram-positive bacteria, but not gram-negative bacteria and fungi. Therefore, our findings suggested that the CBE system might serve as a powerful tool for multiplex genome editing and greatly accelerating the unraveling of hidden antibiotics in Bacillus and Paenibacillus species.

A Cell Membrane Fluorogenic Probe for Gram-Positive Bacteria Imaging and Real-Time Tracking of Bacterial Viability

Bacterial infections are a global healthcare problem, resulting in serious clinical morbidities and mortality. Real-time monitoring of live bacteria by fluorescent imaging technology has potential in diagnosis of bacterial infections, elucidating antimicrobial agents' mode of action, assessing drug toxicity, and examining bacterial antimicrobial resistance. In this work, a naphthalimide-derived fluorescent probe ZTRS-BP was developed for wash-free Gram-positive bacteria imaging. The probe aggregated in aqueous solutions and exhibited aggregation-caused fluorescence quenching (ACQ). The interaction with Gram-positive bacteria cell walls would selectively disaggregate the probe and the liberated probes were dispersed on the outside of the bacteria cell walls to achieve surface fluorescence imaging. There were no such interactions with Gram-negative bacteria, which indicates that selective binding and imaging of Gram-positive bacteria was achieved. The binding of zinc ions by ZTRS-BP can enhance the fluorescent signals on the bacterial surface by inhibiting the process of photoinduced electron transfer. ZTRS-BP-Zn(II) complex was an excellent dye to discriminate mixed Gram-positive and Gram-negative bacteria. Also, live and dead bacteria can be differentially imaged by ZTRS-BP-Zn(II). Furthermore, ZTRS-BP-Zn(II) was used for real-time monitoring bacteria viability such as B. cereus treated with antibiotic vancomycin.

Antibiograms of intensive care units at an Egyptian tertiary care hospital

Background

Intensive care unit (ICU) infection management is a growing challenge, and physicians should have regularly updated antibiograms. The aim of this study was to find out the prevalence of pathogens and to determine their antibiotic susceptibility in different ICUs of an Egyptian tertiary care hospital. This retrospective record-based cross-sectional study was conducted from the first of January to the last of December 2019 with a total of 45,221 diagnostic first-isolate culture/patient obtained from different ICUs in Zagazig University Hospitals. The antibiogram construction was done according to Clinical and Laboratory Standards Institute instructions and a Web-based antibiogram at Stanford University.

Results

The positive blood isolate was the most prevalent infection site (32.37%) followed by sputum and urine isolates. Gram-negative microorganisms (74.41%) were the most common pathogens, with Klebsiella pneumoniae as the most frequently identified one with an incidence of 33.51% followed by Escherichia coli with 19.3% incidence. Antibiotic sensitivity showed that colistin is the most effective antibiotic with 96.2%, 94.7%, and 89.9% sensitivity for Klebsiella, E. coli, and Acinetobacter, respectively, while carbepenems sensitivity was extremely low, showing 19.5% and 19% imipenem and meropenem sensitivity for Klebsiella, 48% imipenem and 52.7% meropenem sensitivity for E. coli, 20.1% imipenem and 20.3% meropenem sensitivity for Acinetobacter, and 17.3% imipenem and 15.2% meropenem sensitivity for Pseudomonas aeruginosa. Fungal infection in our results represented less than 1%.

Conclusion

Our study provides a local baseline epidemiological data which describes the extent of the ICU infections problem in this tertiary care hospital.

Trial registration

ClinicalTrials.gov (NCT04318613)

Copper Sulfide Nanoassemblies for Catalytic and Photoresponsive Eradication of Bacteria from Infected Wounds

Bovine serum albumin (BSA)-encapsulated copper sulfide nanocrystals (CuS NCs) were prepared by heating an alkaline solution containing copper ions and BSA without an additional sulfur source. At a high BSA concentration (0.8 mM), nanoassembly of the as-formed CuS NCs occurs to form BSA-CuS NCs as a result of the formation of BSA gel-like structures. In addition to their intrinsic photothermal properties, the BSA-CuS NCs possess rich surface vacancies and thus exhibit enzyme-like and photodynamic activities. Spontaneous generation of hydrogen peroxide (H₂O₂) led to the in situ formation of copper peroxide (CPO) nanodots on the BSA-CuS NCs to catalyze singlet oxygen radical generation. The antimicrobial response was enhanced by >60-fold upon NIR laser irradiation, which was ascribed to the combined effect of the photodynamic and photothermal inactivation of bacteria. Furthermore, BSA-CuS NCs were transdermally administered onto a methicillin-resistant Staphylococcus aureus-infected wound and eradicated >99% of bacteria in just 1 min under NIR illumination due to the additional peroxidase-like activity of BSA-CuS NCs, transforming H₂O₂ at the infection site into hydroxyl radicals and thus increasing the synergistic effect from photodynamic and photothermal treatment. The BSA-CuS NCs exhibited insignificant in vitro cytotoxicity and hemolysis and thus can serve as highly biocompatible bactericides in preclinical applications to effectively eradicate bacteria.

Implementation of Antibiotic Stewardship in a University Hospital Setting

The article describes activities of an antibiotic center at a university hospital in the Czech Republic and presents the results of antibiotic stewardship program implementation over a period of 10 years. It provides data on the development of resistance of Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa and Staphylococcus aureus to selected antibiotic agents as well as consumption data for various antibiotic classes. The genetic basis of resistance to beta-lactam antibiotics and its clonal spread were also assessed. The study showed significant correlations between aminoglycoside consumption and resistance of Escherichia coli and Klebsiella pneumoniae to gentamicin (r = 0.712, r = 0.869), fluoroquinolone consumption and resistance of Klebsiella pneumoniae to ciprofloxacin (r = 0.896), aminoglycoside consumption and resistance of Pseudomonas aeruginosa to amikacin (r = 0.716), as well as carbapenem consumption and resistance of Pseudomonas aeruginosa to meropenem (r = 0.855). Genotyping of ESBL- positive isolates of Klebsiella pneumoniae and Escherichia coli showed a predominance of CTX-M-type; in AmpC-positive strains, DHA, EBC and CIT enzymes prevailed. Of 19 meropenem-resistant strains of Klebsiella pneumoniae, two were identified as NDM-positive. Clonal spread of these strains was not detected. The results suggest that comprehensive antibiotic stewardship implementation in a healthcare facility may help to maintain the effectiveness of antibiotics against bacterial pathogens. Particularly beneficial is the work of clinical microbiologists who, among other things, approve administration of antibiotics to patients with bacterial infections and directly participate in their antibiotic therapy.

Best practice: antibiotic decision-making in ICUs

PURPOSE OF REVIEW

A major challenge in the ICU is optimization of antibiotic use. This review assesses current understanding of core best practices supporting and promoting astute antibiotic decision-making.

RECENT FINDINGS

Limiting exposure to the shortest effective duration is the cornerstone of antibiotic decision-making. The decision to initiate antibiotics should include assessment of risk for resistance. This requires synthesis of patient-level data and environmental factors to determine whether delayed initiation could be considered in some patients with suspected sepsis until sensitivity data is available. Until improved stratification scores and clinically meaningful cut-off values to identify MDR are available and externally validated, decisions as to which empiric antibiotic is used should rely on syndromic antibiograms and institutional guidance. Optimization of initial and maintenance doses is another enabler of enhanced outcome. Stewardship practices must be streamlined by re-assessment to minimize negative effects, such as a potential increase in duration of therapy and increased risk of collateral damage from exposure to multiple, sequential antibiotics that may ensue from de-escalation.

SUMMARY

Multiple challenges and research priorities for antibiotic optimization remain; however, the best stewardship practices should be identified and entrenched in daily practice. Reducing unnecessary exposure remains a vital strategy to limit resistance development.

Clinical Microbiology in the Intensive Care Unit: Time for Intensivists to Rejuvenate this Lost Art

We live in an era of evolving microbial infections and equally evolving drug resistance among microorganisms. In any healthcare facility, intensivists play the most pivotal role with critically ill patients under their direct care. Majority of the critically ill patients already harbor a microorganism at admission or acquire one in the form of healthcare-associated infections during their course of intensive care unit stay. It is therefore rather imperative for intensivists to possess sound knowledge in clinical microbiology. On a negative note, most clinicians have very meager and remote knowledge acquired during their undergraduate years. This knowledge is rather theoretical than applied and wanes over the years becoming nonbeneficial in intensive patient care. We, therefore, intend to explore important concepts in applied microbiology and infection control that intensivists should know and implement in their clinical practice on a day-to-day basis.

How to cite this article: Princess I, Vadala R. Clinical Microbiology in the Intensive Care Unit: Time for Intensivists to Rejuvenate this Lost Art. Indian J Crit Care Med 2021;25(5):566–574.

Spotlight on New Antibiotics for the Treatment of Pneumonia

In the last years, the presence of multidrug-resistant (MDR) Gram-negative (like Klebsiella pneumoniae, Pseudomonas aeruginosa, Acinetobacter baumannii) and Gram-positive bacteria (mostly methicillin-resistant Staphylococcus aureus) was worldwide reported, limiting the options for an effective antibiotic therapy. For these reasons, inappropriate antimicrobial therapy and delayed prescription can lead to an unfavorable outcome, especially in patients with pneumonia. New antibiotics approved belong to classes of antimicrobials, like beta-lactams with or without beta-lactamase inhibitors, aminoglycosides, oxazolidinones, quinolones, and tetracyclines, or based on new mechanisms of action. These new compounds show many advantages, including a broad spectrum of activity against MDR pathogens, good lung penetration, safety and tolerability, and finally the possibility of intravenous and/or oral formulations. However, the new antibiotics under development represent an important possible armamentarium against difficult-to-treat strains. The safety and clinical efficacy of these future drugs should be tested in clinical practice. In this review, there are reported characteristics of newly approved antibiotics that represent potential future options for the treatment of respiratory tract infections, including those caused by multidrug-resistant bacteria. Finally, the characteristics of the drugs under development are briefly reported.

Incidence, impact and risk factors for multidrug-resistant organisms (MDRO) in patients with major trauma: a European Multicenter Cohort Study

INTRODUCTION

The burden of MDRO in health systems is a global issue, and a growing problem. We conducted a European multicenter cohort study to assess the incidence, impact and risk factors for multidrug-resistant organisms in patients with major trauma. We conducted this study because the predictive factors and effects of MDRO in severely injured patients are not yet described. Our hypothesis is that positive detection of MDRO in severely injured patients is associated with a less favorable outcome.

METHODS

Retrospective study of four level-1 trauma centers including all patients after major trauma with an injury severity score (ISS) ≥ 9 admitted to an intensive care unit (ICU) between 2013 and 2017. Outcome was measured using the Glasgow outcome scale (GOS).

RESULTS

Of 4131 included patients, 95 (2.3%) had a positive screening for MDRO. Risk factors for MDRO were male gender (OR 1.73 [95% CI 1.04-2.89]), ISS (OR 1.01 [95% CI 1.00-1.03]), PRBC's given (OR 1.73 [95% CI 1.09-2.78]), ICU stay > 48 h (OR 4.01 [95% CI 2.06-7.81]) and mechanical ventilation (OR 1.85 [95% CI 1.01-3.38]). A positive MDRO infection correlates with worse outcome. MDRO positive cases GOS: good recovery = 0.6%, moderate disability = 2.1%, severe disability = 5.6%, vegetative state = 5.7% (p < 0.001).

CONCLUSIONS

MDRO in severely injured patients are rare but associated with a worse outcome at hospital discharge. We identified potential risk factors for MDRO in severely injured patients. Based on our results, we recommend a standardized screening procedure for major trauma patients.

The use of antibiotics in the intensive care unit of a tertiary hospital in Malawi

BACKGROUND

Antibiotic resistance is on the rise. A contributing factor to antibiotic resistance is the misuse of antibiotics in hospitals. The current use of antibiotics in ICUs in Malawi is not well documented and there are no national guidelines for the use of antibiotics in ICUs. The aim of the study was to describe the use of antibiotics in a Malawian ICU.

METHODS

A retrospective review of medical records of all admissions to the main ICU in Queen Elizabeth Central Hospital in Blantyre, Malawi, between January 2017 and April 2019. Data were extracted from the ICU patient register on clinical parameters on admission, diagnoses, demographics and antibiotics both prescribed and given for all patients admitted to the ICU. Usage of antibiotics in the ICU and bacterial culture results from samples taken in the ICU and in the peri-ICU period, (from 5 days before ICU admission to 5 days after ICU discharge), were described.

RESULTS

Six hundred-and-forty patients had data available on prescribed and received medications and were included in the analyses. Of these, 577 (90.2%) were prescribed, and 522 (81.6%) received an antibiotic in ICU. The most commonly used antibiotics were ceftriaxone, given to 470 (73.4%) of the patients and metronidazole to 354 (55.3%). Three-hundred-and-thirty-three (52.0%) of the patients received more than one type of antibiotic concurrently - ceftriaxone and metronidazole was the most common combination, given to 317 patients. Forty five patients (7.0%) were given different antibiotics sequentially. One-hundred-and-thirty-seven patients (21.4%) had a blood culture done in the peri-ICU period, of which 70 (11.0% of the patients) were done in the ICU. Twenty-five (18.3%) of the peri-ICU cultures were positive and eleven different types of bacteria were grown in the cultures, of which 17.2% were sensitive to ceftriaxone.

CONCLUSION

We have found a substantial usage of antibiotics in an ICU in Malawi. Ceftriaxone, the last-line antibiotic in the national treatment guidelines, is commonly used, and bacteria appear to show high levels of resistance to it, although blood culture testing is infrequently used. Structured antibiotic stewardship programs may be useful in all ICUs.