Risk Factors of Multidrug-Resistant Bacteria in Lower Respiratory Tract Infections: A Systematic Review and Meta-Analysis

Machine Learning-Based Prediction Model for Multidrug-Resistant Organisms Infections: Performance Evaluation and Interpretability Analysis

Background

Multidrug-resistant organism (MDRO) infections pose a significant global health threat, particularly in intensive care units (ICUs), where delayed identification exacerbates clinical outcomes. Although machine learning (ML) holds promise for infection prediction, the opaque nature of complex algorithms impedes clinical adoption. This study evaluated an interpretable machine learning model incorporating SHapley Additive exPlanations (SHAP) to predict MDRO infections in ICU patients.

Methods

A retrospective cohort study was conducted on 888 ICU patients (2020-2022) from a tertiary hospital in China. Following TRIPOD guidelines, key predictors were identified using Lasso regression from a comprehensive set of clinical variables, including demographics, treatments, and laboratory data. Six machine learning algorithms-Neural Networks, Random Forests, Support Vector Machines, Logistic Regression, Decision Trees, and Gaussian Naive Bayes-were evaluated based on AUC, accuracy, and calibration curves. SHAP analysis provided both global and local interpretability.

Results

Among 825 eligible cases (375 MDRO infections), the Random Forest model exhibited the highest performance (AUC = 0.83, accuracy = 76.7%). SHAP analysis identified urinary catheterization, ventilator use, and prolonged antibiotic exposure as key modifiable risk factors. Case-level interpretation via dynamic force plots illustrated individualized risk stratification. Decision curve analysis indicated clinical utility within probability thresholds of 0.44-0.60.

Conclusion

This study establishes an interpretable prediction framework integrating RF algorithms with SHAP explainability, balancing predictive accuracy with clinical transparency. The model's dynamic visualization capabilities support individualized risk assessment and evidence-based antimicrobial stewardship. Integration into hospital information systems with real-time dashboards could enhance early intervention strategies.

Treatment with Ceftazidime-Avibactam for Lower Respiratory Tract Infections Caused by the Multidrug-Resistant Gram-Negative Bacteria in the Intensive Care Unit

Purpose

Ceftazidime avibactam (CAZ-AVI) is recommended for treating severe infections caused by multidrug-resistant gram-negative bacteria (MDR-GNB). However, there are few real-world studies on the use of CAZ-AVI to treat lower respiratory tract infections (LRTIs) caused by MDR-GNBs in intensive care units (ICUs). This study aimed to evaluate the clinical characteristics of patients with LRTIs caused by MDR-GNB who were treated with CAZ-AVI in the ICU, and to investigate the independent risk factors for mortality.

Patients and Methods

This single-center retrospective study included patients with LRTIs treated with CAZ-AVI in the respiratory ICU of a tertiary hospital in Anhui Province between December 2022 and November 2024. The primary outcomes were 28-day survival and independent risk factors for all-cause mortality.

Results

A total of 71 patients were enrolled in the study and 56.3% (40/71) had 28-day survival outcomes. The Acute Physiology and Chronic Health Evaluation (APACHE) II score (odds ratio [OR]: 1.144, 95% confidence interval [CI]: 1.012-1.293, p=0.032), coinfection with Aspergillus (OR: 42.753, 95% CI: 2.324-786.555, p=0.011), and days of CAZ-AVI (OR: 0.851, 95% CI: 0.734-0.986, p=0.032) were independent risk factors for 28-day all-cause mortality. Kaplan-Meier analysis demonstrated prolonged CAZ-AVI therapy (>10 days) improved survival (p<0.001), APACHE II scores >24 correlated with increased 28-day mortality (p=0.0048), and Aspergillus coinfection significantly reduced survival rates (p=0.001). We also constructed a nomogram for predicting the risk of death in ICU patients treated with CAZ-AVI for LRTIs, with good discrimination and calibration.

Conclusion

CAZ-AVI can be used to treat LRTIs caused by MDR-GNB in the ICU. Higher APACHE II scores and coinfection with Aspergillus were associated with 28-day mortality, whereas a longer course of therapy was a protective factor. The nomogram can help clinicians predict CAZ-AVI outcomes.

Factors Associated With Multi-Drug Resistant Organisms Among Bronchiectasis Patients: A Retrospective Study of Bronchiectasis Patients in Jordan

Background

Bronchiectasis, a respiratory ailment, significantly impacts the life expectancy of individuals. This study aimed to explore the prevalence of multidrug-resistant organisms (MDROs) among bronchiectasis patients, the resistance patterns within various antibiotic classes, and the associated factors with these organisms.

Methods

A retrospective observational analysis was conducted on adult bronchiectasis patients attending clinics at Jordan University Hospital. The diagnosis of bronchiectasis was established through lung Computerized Tomography (CT) scans and clinical symptom assessment.

Results

The study encompassed 235 patients, revealing a notably higher occurrence of MDROs among non-cystic fibrosis patients compared to their counterparts (P-value=0.001). Additionally, MDROs showed significant associations with the usage of inhaled beta agonists, anti-cholinergics, corticosteroids, and inhaled antibiotics (P-value<0.050). Patients with MDROs experienced a significantly elevated mean number of hospitalizations, exacerbations, and antibiotic courses compared to their counterparts (P-value<0.050). Moreover, those with MDROs exhibited a higher incidence of requiring O2 device support and faced an increased risk of mortality (P-value<0.050).

Conclusion

The observational nature of our study limits the associations in our study. However, we provided evidence that it is imperative for clinicians to assess their bronchiectasis patients for MDRO risk factors, facilitating appropriate initial antibiotic selection. Nevertheless, the validation of MDRO risk factors necessitates further exploration through larger studies with extended follow-up periods.

Risk factors for drug-resistant pathogens in community-acquired pneumonia: systematic review and meta-analysis

INTRODUCTION

Community-acquired pneumonia (CAP) is a leading cause of death worldwide. Reducing inappropriate and excessive use of extended-spectrum antibiotics is essential for treating CAP effectively. Evaluating the risk of drug-resistant pathogens (DRPs) is crucial for determining initial antibiotic therapy in clinical settings.

METHODS

This systematic review and meta-analysis assessed the risk factors for DRPs in patients with CAP. CAP-DRPs were defined as pathogens resistant to commonly used antibiotics for CAP, including nonpseudomonal β-lactams such as ceftriaxone or sulbactam-ampicillin, macrolides and respiratory fluoroquinolones. The studies included were divided into two cohorts, namely an all-patient cohort, comprising both culture-positive and culture-negative patients, and a culture-positive pneumonia cohort, comprising patients with identified causative pathogens. The primary objective of this study was to evaluate the risk factors for CAP-DRPs in the all-patient cohort.

RESULTS

24 articles were included with 11 categorised into the all-patient cohort. The meta-analysis identified 11 significant risk factors for CAP-DRPs, namely prior DRP infection/colonisation, tracheostomy, severe respiratory failure requiring early induction of mechanical ventilation, prior use of antibiotics, chronic lung disease, COPD, wound care, neurological disorders, prior hospitalisation, nursing home residence and low activities of daily living.

CONCLUSION

To our knowledge, this is the first systematic review focused on CAP-DRP. Unlike previous reviews, the all-patient and culture-positive pneumonia cohorts were analysed separately. Findings from the all-patient cohort are particularly relevant for guiding initial antimicrobial selection in clinical practice. Furthermore, the abovementioned factors should be considered when developing prediction models for CAP-DRPs.

Endophytic Penicillium oxalicum AUMC 14898 from Opuntia ficus-indica: A Novel Source of Tannic Acid Inhibiting Virulence and Quorum Sensing of Extensively Drug-Resistant Pseudomonas aeruginosa

Pseudomonas aeruginosa is a harmful pathogen that causes a variety of acute and chronic infections through quorum sensing (QS) mechanisms. The increasing resistance of this bacterium to numerous antibiotics has created a demand for new medications that specifically target QS. Endophytes can be the source of compounds with antibacterial properties. This research is the first to examine tannic acid (TA) produced by endophytic fungus as a potential biotherapeutic agent. A novel endophytic fungal isolate identified as Penicillium oxalicum was derived from the cladodes of Opuntia ficus-indica (L.). The species identification for this isolate was confirmed through sequencing of the internal transcribed spacer region. The metabolites from the culture of this isolate were extracted using ethyl acetate, then separated and characterized using chromatographic methods. This led to the acquisition of TA, a compound that shows strong anti-QS and excellent antibacterial effects against extensively drug-resistant P. aeruginosa strains. Furthermore, it was shown that treating P. aeruginosa with the obtained TA reduced the secretion of virulence factors controlled by QS in a dose-dependent manner, indicating that TA inhibited the QS characteristics of P. aeruginosa. Simultaneously, TA significantly inhibited the expression of genes associated with QS, including rhlR/I, lasR/I, and pqsR. In addition, in silico virtual molecular docking showed that TA could efficiently bind to QS receptor proteins. Our results showed that P. oxalicum could be a new source of TA for the treatment of infections caused by extensively drug-resistant P. aeruginosa.

Development and validation of a novel prediction model for Carbapenem-resistant organism infection in a large-scale hospitalized patients

Carbapenem-resistant organism (CRO) are defined as gram-negative bacteria. The lack of safe and effective antibiotics has led to an increase in incidence rate. The purpose of this study is to establish and determine a risk nomogram to predict CRO infection in hospitalized patients. Hospitalized patients' information were collected from the electronic medical record system of hospital between January 2019 and December 2022. Based on the inclusion and exclusion criteria, we identified 131390 inpatients who met the criteria for this study. For the training cohort, the area under the curves (AUC) for predicting the CRO infection was 0.935. For the validation cohort, the AUC for predicting the CRO infection was 0.937. We have developed the first novel nomogram to predict CRO infection in hospitalized patients, which is reliable and high-performance. The nomogram performs well among hospitalized patients and has good predictive ability.

A Nomogram for Predicting the Effectiveness of Consultations on Multi-Drug Resistant Infections: An Exploration for Clinical Pharmacy Services

Purpose

The increasing multi-drug resistance (MDR) is a serious threat to human health. The appropriate use of antibiotics can control the progression of MDR and clinical pharmacists play an important role in the rational use of antibiotics. There are many factors that influence the effectiveness of multi-drug resistant organisms (MDRO) infection consultations. The study aimed to establish a model to predict the outcome of consultation and explore ways to improve clinical pharmacy services.

Patients and methods

Patients diagnosed with MDRO infection and consulted by clinical pharmacists were included. Univariate analysis and multivariate logistic regression analysis were used to identify independent risk factors for MDRO infection consultation effectiveness, and then a nomogram was constructed and validated.

Results

198 patients were finally included. The number of underlying diseases (OR=1.720, 95% CI: 1.260-2.348), whether surgery was performed prior to infection (OR=8.853, 95% CI: 2.668-29.373), ALB level (OR=0.885, 95% CI: 0.805~0.974), pharmacist title (OR=3.463, 95% CI: 1.277~9.396) and whether the recommendation was taken up (OR=0.117, 95% CI: 0.030~0.462) were identified as independent influences on the effectiveness of the consultation. The nomogram prediction model was successfully constructed and the AUC of the training set and the verification set were 0.849 (95% CI: 0.780-0.917) and 0.761 (95% CI: 0.616-0.907) respectively. The calibration curves exhibited good overlap between the data predicted by the model and the actual data.

Conclusion

A nomogram model was developed to predict the risk of consultation failure and was shown to be good accuracy and good prediction efficiency, which can provide proactive interventions to improve outcomes for potentially treatment ineffective patients.

Antimicrobial Resistance Patterns of Common Gram-Negative Microorganisms Isolated from Patients with Lower Respiratory Tract Infections in a Teaching Hospital in Vietnam

This cross-sectional study investigated the antimicrobial resistance (AMR) patterns of gram-negative pathogens isolated from 4,789 hospitalized patients with lower respiratory tract infections (LRTIs). Of the collected specimens, 1,325 (27.7%) tested positive for gram-negative bacteria. Acinetobacter baumannii (38.6%), Pseudomonas aeruginosa (33.5%), Klebsiella pneumoniae (18.7%), Escherichia coli (5.6%), and Klebsiella aerogenes (3.5%) were the most prevalent isolates. AMR analysis revealed high resistance rates (79.9%-100%) of A. baumannii isolates to multiple classes of antibiotics except amikacin, trimethoprim/sulfamethoxazole, and colistin. P. aeruginosa displayed low resistance to colistin (< 10%) but high resistance to other antibiotics. K. pneumoniae displayed high resistance rates of 90.0%-100.0% to most penicillins, whereas resistance rates were notably lower for colistin (7.1%) and amikacin (16.7%). K. aerogenes exhibited high resistance to various antibiotics and sensitivity to amikacin (95.1%), ampicillin (100.0%), and colistin (100.0%). E. coli isolates exhibited resistance to ampicillin (96.9%) and maximum sensitivity to several antibiotics. Our study identified significant AMR trends and highlighted the prevalence of multidrug-resistant strains (93.6% for K. aerogenes and 69.1%-92.4% for other isolates). These findings emphasize the urgent need for appropriate antibiotic management practices to combat AMR in gram-negative pathogens associated with LRTIs.

Comparative performance of biofire pneumonia panel and standard culture-based methods for diagnosing pneumonia in critically ill patients: Impact on antibiotic stewardship

INTRODUCTION

Lower respiratory tract infections (LRTIs) are a common cause of morbidity and mortality worldwide. Accurate identification of the pathogens causing LRTIs is crucial for ensuring of diagnostic and antibiotic stewardship. The Biofire Pneumonia Panel (BFPP) is a molecular diagnostic test that allows rapid detection of various bacterial and viral pathogens. In this study, we compared the performance of BFPP with standard culture methods for the detection of pathogens.

MATERIALS AND METHODS

Respiratory samples from 70 patient with suspected LRTIs were tested using both BFPP and standard culture methods. The distribution of isolated bacterial pathogens was analyzed, and the sensitivity and specificity of BFPP were calculated. Additionally, the performance of BFPP in detecting antimicrobial resistance genes was evaluated. The results were compared with those obtained from VITEK-2 antimicrobial susceptibility testing and culture-based methods.

RESULTS

Among the suspected LRTI cases, BFPP identified a single pathogen in 32.8% of cases and multiple pathogens in 40% of cases. The standard culture method detected a single pathogen in 47.1% of cases. BFPP showed a sensitivity of 93.9% and a specificity of 45.9% for the total sample. The performance of BFPP in detecting antimicrobial resistance genes varied for different pathogens with overall sensitivity of 40.1% and specificity of 95.9%.

CONCLUSION

The Biofire Pneumonia Panel (BFPP) demonstrated high sensitivity for several bacterial pathogens, indicating its potential as a rapid diagnostic tool. However, its performance varied for different microorganisms, and it had limitations in detecting certain pathogens and antimicrobial resistance genes for which still required more further studies to explore different resistance gene mechanism that can be incorporated in this panel in future. The BFPP can complement standard culture methods as a rapid tool in the diagnosis of LRTIs.

Colonization with extended spectrum beta-lactamase and carbapenemases producing Enterobacteriaceae among hospitalized patients at the global level: A systematic review and meta-analysis

BACKGROUND

Gut commensal bacteria can mediate resistance against pathogenic bacteria. However, exposure to antibiotics and hospitalization may facilitate the emergence of multidrug resistant bacteria. We aimed to conduct a systematic review and meta-analysis to provide comprehensive evidence about colonization rate of extended spectrum beta-lactamase and carbapenemases producing Enterobacteriaceae.

METHOD

We used PubMed, Google Scholar and Web of Science data bases to search studies from January 1, 2016 to August10, 2022 about colonization rate of extended spectrum beta-lactamase and carbapenemase producing Enterobacteriaceae. Data were extracted from eligible studies and analyzed using Stata version 16 software. The quality of included studies was assessed using the Joanna Briggs Institute Critical Appraisal tools, and publication bias was assessed using funnel plot and eggers test.

RESULTS

We identified 342 studies from the comprehensive data search and data were extracted from 20 studies. The pooled estimate of extended spectrum beta-lactamase and carbapenemase producing Enterobacteriaceae were 45.6%(95%CI: 34.11-57-10) and 16.19% (95% CI: 5.46-26.91) respectively. The predominant extended spectrum beta-lactamase producers were E. coli,32.99% (95% CI: 23.28-42.69) and K. pneumoniae, 11.43% (95% CI:7.98-14.89). Prolonged hospitalization was linked to carbapenemase producing Enterobacteriaceae colonization with the odds of 14.77 (95% CI: -1.35-30.90) at admission and 45.63 (95% CI: 0.86-92.12) after ≥7 days of admission.

CONCLUSION

The pooled estimate of extended spectrum beta-lactamase and carbapenemase producing Enterobacteriaceae were high. This indicates the need for strong mitigation strategies to minimize the spread of multidrug-resistant bacteria at the healthcare facilities.

Increase in Incidence Rates and Risk Factors for Multidrug Resistant Bacteria in Septic Children: A Nationwide Spanish Cohort Study (2013-2019)

The emergence of multidrug-resistant (MDR) bacteria in children is a growing concern, particularly among septic patients, given the need for first-right dosing. Our aim was to determine the incidence rates and factors associated with MDR-sepsis in the pediatric intensive care unit (PICU), using data from the Spanish ENVIN-HELICS PICU registry between 2013 and 2019. The rate of MDR bacteria among septic children ranged between 5.8 and 16.2% throughout this study period, with a significant increase since 2015 (p = 0.013). MDR-gram-negative bacteria (92%), particularly EBL-Enterobacterales (63.7%), were the most frequent causative microorganisms of MDR-sepsis. During this study period, sixteen MDR-sepsis (32.6%) corresponded to intrahospital infections, and 33 (67.4%) had community-onset sepsis, accounting for 10.5% of the overall community-onset sepsis. Independent risk factors associated with MDR-sepsis were antibiotics 48 h prior to PICU admission (OR 2.38) and PICU onset of sepsis (OR 2.58) in >1 year-old children, and previous malnourishment (OR 4.99) in <1 year-old children. Conclusions: There was an alarming increase in MDR among septic children in Spain, mainly by gram-negative (ESBL-Enterobacterales), mostly coming from the community setting. Malnourished infants and children on antibiotics 48 h prior to PICU are at increased risk and therefore require closer surveillance.

Clinical efficacy of Buzhong Yiqi decoction in the treatment of hospital-acquired pneumonia with multi-drug resistant bacteria: a prospective, randomized, multicenter controlled trial

OBJECTIVE

To evaluate the efficacy and safety of Buzhong Yiqi decoction (, BZYQ) in the treatment of hospital-acquired pneumonia (HAP) with multi-drug-resistant bacteria (MDRB).

METHODS

This 28-day study was conducted at 5 clinical centers in Shanghai. The eligible patients were randomly assigned (1:1) into the intervention group (BZYQ plus conventional Western Medicine therapy) and control group (conventional Western Medicine therapy). The primary outcomes were the clinical response, clinical pulmonary infection score (CPIS), and microbiologic response. The secondary outcomes were the 28-day all-cause mortality (ACM), Acute Physiology and Chronic Health Evaluation Ⅱ (APACHE Ⅱ) score, ventilator weaning rate, length of mechanical ventilation (MV), length of hospital stay, and changes of infection indicators.

RESULTS

Altogether 83 subjects in the intervention group and 85 subjects in the control group were analyzed. The clinical success rate (48.2%) and the pathogen eradication rate (59.0%) of the intervention group were all better than those of the control group (32.9% and 38.9%, respectively) with statistically significant differences (<0.05). The CPIS score of the intervention group (8.9 ± 1.7) was lower than that of the control group (9.6 ± 2.5) (<0.05). The length of MV in the intervention group [(13.7 ± 6.4) d] was significantly shorter than that of the control group [ (17.2 ± 7.2) d] (<0.05). The 28-day ACM of the intervention group (13.33%) was lower than that of the control group (21.2%) with no statistically significant difference (>0.05). The differences between two groups in ventilator weaning rate, length of hospital stay, and APACHE Ⅱ score were not statistically significant (> 0.05). The intervention group displayed decreases in white blood cell count, C-reactive protein, neutrophil percentage, and procalcitonin at day 28 compared with baseline (<0.05). No serious adverse events occurred in either group during the 28-day follow-up.

CONCLUSION

BZYQ may be an effective therapeutic option for the management of HAP with MDRB.

Microbial Landscape and Antibiotic-Susceptibility Profiles of Microorganisms in Patients with Bacterial Pneumonia: A Comparative Cross-Sectional Study of COVID-19 and Non-COVID-19 Cases in Aktobe, Kazakhstan

This cross-sectional study investigated the microbial landscape and antibiotic-resistance patterns in patients with bacterial pneumonia, with a focus on the impact of COVID-19. Sputum samples from individuals with bacterial pneumonia, including coronavirus disease 2019-positive polymerase chain reaction (COVID-19-PCR+), COVID-19-PCR- and non-COVID-19 patients, were analyzed. Surprisingly, the classic etiological factor of bacterial pneumonia, Streptococcus pneumoniae, was rarely isolated from the sputum samples. Furthermore, the frequency of multidrug-resistant pathogens was found to be higher in non-COVID-19 patients, highlighting the potential impact of the pandemic on antimicrobial resistance. Strains obtained from COVID-19-PCR+ patients exhibited significant resistance to commonly used antibiotics, including fluoroquinolones and cephalosporins. Notably, the ESKAPE pathogens, Staphylococcus aureus, Klebsiella pneumoniae, Pseudomonas aeruginosa, Enterobacter cloacae, and Enterobacter aerogenes, were identified among the isolated microorganisms. Our findings underscore the urgent need for infection control measures and responsible antibiotic use in healthcare settings, as well as the importance of enhancing pneumonia diagnostics and implementing standardized laboratory protocols.

Management of Bacterial and Fungal Infections in the ICU: Diagnosis, Treatment, and Prevention Recommendations

Bacterial and fungal infections are common issues for patients in the intensive care unit (ICU). Large, multinational point prevalence surveys have identified that up to 50% of ICU patients have a diagnosis of bacterial or fungal infection at any one time. Infection in the ICU is associated with its own challenges. Causative organisms often harbour intrinsic and acquired mechanisms of drug-resistance, making empiric and targeted antimicrobial selection challenging. Infection in the ICU is associated with worse clinical outcomes for patients. We review the epidemiology of bacterial and fungal infection in the ICU. We discuss risk factors for acquisition, approaches to diagnosis and management, and common strategies for the prevention of infection.

Airway multidrug-resistant organisms in a population of tracheostomy and chronic ventilator-dependent children at a tertiary care pediatric hospital

OBJECTIVE/BACKGROUND

Children with tracheostomies are at an increased risk of bacterial respiratory tract infections. Infections caused by multidrug-resistant organisms (MDROs) are more difficult to treat and can result in severe complications. This study aimed to investigate the risk factors and sequelae of MDRO positivity in tracheostomy and chronic ventilator-dependent children.

METHODS

We performed a retrospective chart review of 75 tracheostomy and chronic ventilator-dependent children at St. Louis Children's Hospital. Data on demographics, respiratory cultures, hospitalizations, emergency department (ED) visits, and antibiotic usage were collected. We determined the frequency of MDRO positivity and compared the number of hospitalizations, number of ED visits, and antibiotic usage in patients with and without MDRO-positive cultures. Patient clinical variables were analyzed before and after MDRO acquisition.

RESULTS

We found 75.7% (56/74) of our participants had an MDRO-positive culture, with methicillin-resistant Staphylococcus aureus (MRSA, n = 36, 64%) and Pseudomonas aeruginosa (n = 8, 14%) being the most commonly detected organisms. Participants with a greater number of annual nonpulmonary admissions (odds ratio [OR] = 1.99, 95% confidence interval [CI] (1.21-3.29), p = 0.008], inpatient antibiotic courses [OR = 1.27, 95% CI (1.07-1.50), p = 0.006], total antibiotic courses [OR = 1.26, 95% CI (1.08-1.48), p = 0.004], and chronic antibiotic use [OR = 2.31, 95% CI (1.12-4.74), p = 0.03] were at an increased risk for MDRO positivity. Those who were MDRO-positive had more pulmonary admissions following MDRO acquisition compared those who were MDRO-negative [p = 0.005] but not more antibiotic usage or ED visits.

CONCLUSION

Frequent antibiotic usage and hospitalizations increase the risk of MDRO acquisition in children with tracheostomies and ventilator-dependence. Further antibiotic stewardship may help prevent resistant infections in technology-dependent children.

The health facility as a risk factor for multidrug-resistant gram-negative bacteria in critically ill patients with COVID-19

BACKGROUND

The relationship between Multidrug Resistant-Gram Negative Bacteria (MDR-GNB) infection and colonization in critically ill COVID-19 patients has been observed, however, it is still poorly understood. This study evaluated the risk factors for acquiring MDR-GNB in patients with severe COVID-19 in Intensive Care Units (ICU).

METHODS

This is a nested case-control study in a cohort of 400 adult patients (≥ 18 years old) with COVID-19, hospitalized in the ICU of 4 hospitals in the city of Curitiba, Brazil. Cases were critical COVID-19 patients with one or more MDR GNB from any surveillance and/or clinical cultures were taken during their ICU stay. Controls were patients from the same units with negative cultures for MDR-GNB. Bivariate and multivariate analyses were done.

RESULTS

Sixty-seven cases and 143 controls were included. Independent risk factors for MDR bacteria were: male gender (OR = 2.6; 95% CI 1.28‒5.33; p = 0.008); the hospital of admission (OR = 3.24; 95% CI 1.39‒7.57; p = 0.006); mechanical ventilation (OR = 25.7; 95% CI 7.26‒91; p < 0.0001); and desaturation on admission (OR = 2.6; 95% CI 1.27‒5.74; p = 0.009).

CONCLUSIONS

Male gender, desaturation, mechanical ventilation, and the hospital of admission were the independent factors associated with MDR-GNB in patients in the ICU with COVID-19. The only modifiable factor was the hospital of admission, where a newly opened hospital posed a higher risk. Therefore, coordinated actions toward a better quality of care for critically ill COVID-19 patients are essential.

Pulmonary surfactant and drug delivery: vehiculization of a tryptophan-tagged antimicrobial peptide over the air-liquid interfacial highway

This work evaluates interaction of pulmonary surfactant (PS) and antimicrobial peptides (AMPs) in order to investigate (i) if PS can be used to transport AMPs, and (ii) to what extent PS interferes with AMP function and vice versa. This, in turn, is motivated by a need to find new strategies to treat bacterial infections in the airways. Low respiratory tract infections (LRTIs) are a leading cause of illness and death worldwide that, together with the problem of multidrug-resistant (MDR) bacteria, bring to light the necessity of developing effective therapies that ensure high bioavailability of the drug at the site of infection and display a potent antimicrobial effect. Here, we propose the combination of AMPs with PS to improve their delivery, exemplified for the hydrophobically end-tagged AMP, GRR10W4 (GRRPRPRPRPWWWW-NH₂), with previously demonstrated potent antimicrobial activity against a broad spectrum of bacteria under various conditions. Experiments using model systems emulating the respiratory interface and an operating alveolus, based on surface balances and bubble surfactometry, served to demonstrate that a fluorescently labelled version of GRR10W4 (GRR10W4-F), was able to interact and insert into PS membranes without affecting its biophysical function. Therefore, vehiculization of the peptide along air-liquid interfaces was enabled, even for interfaces previously occupied by surfactants layers. Furthermore, breathing-like compression-expansion dynamics promoted the interfacial release of GRR10W4-F after its delivery, which could further allow the peptide to perform its antimicrobial function. PS/GRR10W4-F formulations displayed greater antimicrobial effects and reduced toxicity on cultured airway epithelial cells compared to that of the peptide alone. Taken together, these results open the door to the development of novel delivery strategies for AMPs in order to increase the bioavailability of these molecules at the infection site via inhaled therapies.

Gram-negative multidrug-resistant organisms were dominant in neurorehabilitation ward patients in a general hospital in southwest China

This study aimed to investigate the prevalence of and risk factors for multidrug-resistant organism (MDRO) infection in the rehabilitation ward of a general hospital in Southwest China. We analyzed rehabilitation patients with nosocomial infections caused by MDROs from June 2016 to June 2020. MDRO infection pathogens and associated antibiotic resistance were calculated. Possible risk factors for MDRO-related infection in the neurorehabilitation ward were analyzed using chi-square, and logistic regression. A total of 112 strains of MDRO were found positive from 96 patients. The MDRO test-positive rate was 16.70% (96/575). Ninety-five MDRO strains were detected in sputum, of which 84.82% (95/112) were gram-negative bacteria. Acinetobacter baumannii (A. Baumannii), Pseudomonas aeruginosa (P. aeruginosa), and Klebsiella pneumonia (K. pneumonia) were the most frequently isolated MDRO strains. The logistic regression model and multifactorial analysis showed that long-term (≥ 7 days) antibiotic use (OR 6.901), history of tracheotomy (OR 4.458), and a low albumin level (< 40 g/L) (OR 2.749) were independent risk factors for the development of MDRO infection in patients in the rehabilitation ward (all P < 0.05). Gram-negative MRDOs were dominant in rehabilitation ward patients. Low albumin, history of a tracheostomy, and long-term use of antibiotics were independent risk factors for MRDO infection and are worthy of attention.

Multi-drug resistant gram-negative bacterial pneumonia: etiology, risk factors, and drug resistance patterns

Bacterial pneumonia is one of the most serious public health issues owing to its medical and economic costs, which result in increased morbidity and mortality in people of all ages around the world. Furthermore, antimicrobial resistance has risen over time, and the advent of multi-drug resistance in GNB complicates therapy and has a detrimental impact on patient outcomes. The current review aimed to summarize bacterial pneumonia with an emphasis on gram-negative etiology, pathogenesis, risk factors, resistance mechanisms, treatment updates, and vaccine concerns to tackle the problem before it causes a serious consequence. In conclusion, the global prevalence of GNB in CAP was reported 49.7% to 83.1%, whereas in VAP patients ranged between 76.13% to 95.3%. The most commonly reported MDR-GNB causes of pneumonia were A. baumannii, K. pneumoniae, and P. aeruginosa, with A. baumannii isolated particularly in VAP patients and the elderly. In most studies, ampicillin, tetracyclines, amoxicillin-clavulanic acid, cephalosporins, and carbapenems were shown to be highly resistant. Prior MDR-GNB infection, older age, previous use of broad-spectrum antibiotics, high frequency of local antibiotic resistance, prolonged hospital stays, ICU admission, mechanical ventilation, and immunosuppression are associated with the MDR-GNB colonization. S. maltophilia was reported as a severe cause of HAP/VAP in patients with mechanically ventilated and having hematologic malignancy due to its ability of biofilm formation, site adhesion in respiratory devices, and its intrinsic and acquired drug resistance mechanisms. Effective combination therapies targeting PDR strains and drug-resistant genes, antibiofilm agents, gene-based vaccinations, and pathogen-specific lymphocytes should be developed in the future.

Evaluation of the BioFire FilmArray Pneumonia Panel Plus to the Conventional Diagnostic Methods in Determining the Microbiological Etiology of Hospital-Acquired Pneumonia

Hospital-acquired pneumonia (HAP) is a substantial public health issue that is associated with high mortality rates and is complicated by an arsenal of microbial etiologies, expressing multidrug-resistant phenotypes, rendering relatively limited therapeutic options. BioFire FilmArray Pneumonia Panel plus (BFPP) is a simple multiplexed PCR system that integrates sample preparation, nucleic acid extraction, amplification, and analysis of microbial etiology, with a turnaround time of about one hour. In comparison to standard culture methods, BFPP is simpler, easier to perform, and can simultaneously detect the most common pathogens involved in lower respiratory tract infections (34 targets). Accordingly, we evaluated the diagnostic performance of the multiplexed BFPP for the rapid detection of 27 clinically relevant respiratory pathogens and 7 genetic markers among 50 HAP cases admitted to the intensive care unit (ICU), who submitted mini-bronchoalveolar (mBAL) specimens. In comparison to standard culture methods, BFPP showed an overall sensitivity of 100% [95% CI; 90-100] and overall specificity of 90% [95% CI; 87.4-92.5] among all the tested bacterial targets. BFPP identified 11 viral targets (22%) among the tested specimens. The BFPP semi-quantitative analysis showed a concordance rate of 47.4% among positive culture specimens. For the investigation of the antibiotic resistance genes, BFPP showed a positive percent agreement (PPA), a negative percent agreement (NPA), and an overall percent agreement (OPA), reaching 97% [95% CI; 90-100], 95% [95% CI; 91.5-97], and 95% [95% CI; 93-97], respectively, with standard antibiotic sensitivity testing. In conclusion, BFPP has the potential to enhance the rapid microbiological diagnosis of HAP cases, and could aid in tailoring appropriate antibiotic therapies.

Top 10 Pearls for the Recognition, Evaluation, and Management of Maternal Sepsis

Maternal sepsis is a leading cause of preventable maternal mortality that requires early recognition, expedient evaluation, and appropriate management.

Maternal sepsis is an obstetric emergency and a leading cause of maternal morbidity and mortality. Early recognition in a pregnant or postpartum patient can be a challenge as the normal physiologic changes of pregnancy may mask the signs and symptoms of sepsis. Bedside assessment tools may aid in the detection of maternal sepsis. Timely and targeted antibiotic therapy and fluid resuscitation are critical for survival in patients with suspected sepsis. Once diagnosed, a search for etiologies and early application of source control measures will further reduce harms. If the patient is in septic shock or not responding to initial treatment, multidisciplinary consultation and escalation of care is necessary. Health care professionals should be aware of the unique complications of sepsis in critically ill pregnant and postpartum patients, and measures to prevent poor outcomes in this population. Adverse pregnancy outcomes may occur in association with sepsis, and should be anticipated and prevented when possible, or managed appropriately when they occur. Using a standardized approach to the patient with suspected sepsis may reduce maternal morbidity and mortality.

Severe adverse events in children with tracheostomy and home mechanical ventilation - Comparison of pediatric home care and a specialized pediatric nursing care facility

BACKGROUND

Advances in medical care and ventilator technologies increase the number of children with tracheostomy and home mechanical ventilation (HMV). Data on severe adverse events in home care and in specialized nursing care facilities are limited.

PATIENTS AND METHODS

Retrospective analysis of incidence and type of severe adverse events in children with tracheostomy and HMV in home care compared to a specialized nursing care facility over a 7-year period.

RESULTS

163.9 patient-years in 70 children (home care: 110.7 patient-years, 24 patients; nursing care facility: 53.2 patient-years, 46 patients) were analyzed. In 34 (48.6%) patients tracheostomy was initiated at the age of <1 year. 35 severe adverse events were identified, incidence of severe adverse events per patient-year was 0.21 (median 0.0 (0.0-3.0)). We observed no difference in the rate of severe adverse events between home care and specialized nursing care facility (0.21 [y-1]; median 0.0 (0.0-3.0) versus 0.23 [y-1]; median 0.0 (0.0-1.6); p = 0.690), however, significantly more tracheostomy related incidents and infections occurred in the home care setting. Young age (<1 year) (Odds ratio 3.27; p = 0.045) and feeding difficulties (nasogastric tubes and percutaneous endoscopic gastrostomy) (Odds ratio 9.08; p = 0.016) significantly increased the risk of severe adverse events. Furthermore, the rate of severe adverse events was significantly higher in patients with a higher nursing score.

CONCLUSION

Pediatric home mechanical ventilation via tracheostomy is rarely associated with emergencies or adverse events in home care as well as in a specialized nursing care facility setting.