Management of Adults With Hospital-acquired and Ventilator-associated Pneumonia: 2016 Clinical Practice Guidelines by the Infectious Diseases Society of America and the American Thoracic Society

Re-Thinking the Norms of Antibiotic Prescribing in the Neonatal Intensive Care Unit

Antibiotics are among the most commonly prescribed medications in neonatal care. Newborns are particularly vulnerable to severe infections and the adverse effects associated with inappropriate antibiotic use. Antibiotic stewardship programs are designed to actively monitor antimicrobial resistance, encourage the judicious use of antibiotics, and collaborate with infection control programs and pharmacy departments to curb the spread of resistant organisms. In this article, the authors will examine studies assessing the impact of excessive antibiotic use and explore the effectiveness of various stewardship strategies aimed at reducing unnecessary antibiotic consumption.

Comparing mini bronchoalveolar lavage and endotracheal aspirate in diagnosing bacterial pneumonia in the intensive care unit

Objectives

Pneumonia is a major cause of morbidity and mortality among patients in the intensive care unit (ICU). Timely and accurate diagnosis is crucial for effective treatment, but lower respiratory tract sampling techniques vary in sensitivity and specificity. This study aims to compare the diagnostic accuracy of endotracheal aspirate (ETA) with mini bronchoalveolar lavage (mBAL) in detecting bacterial pneumonia in intubated patients, assessing sensitivity, specificity, positive predictive value (PPV), and negative predictive value (NPV) of ETA against mBAL, the gold standard.

Methods

A cross-sectional comparative study was conducted at the ICU of Sindh Institute of Urology and Transplantation (SIUT), Karachi, Pakistan, over 7 months. Adult patients on mechanical ventilation with suspected or confirmed pneumonia were included. Both mBAL and ETA samples were collected under strict aseptic conditions.

Results

Out of 120 patients, 112 paired samples were analyzed. ETA exhibited a sensitivity of 81.1%, specificity of 92.1%, PPV of 95.2%, and NPV of 71.4%, with an overall accuracy of 84.8%. The most commonly isolated pathogens were Acinetobacter and Klebsiella. No serious adverse events occurred.

Conclusion

ETA is a cost-effective and reliable alternative to mBAL for diagnosing bacterial pneumonia in intubated ICU patients, but clinicians should carefully interpret negative results.

Comparison of trimethoprim-sulfamethoxazole versus minocycline monotherapy for treatment of Stenotrophomonas maltophilia pneumonia

OBJECTIVE

To compare the rate of clinical cure and adverse effects in patients receiving definitive treatment with trimethoprim-sulfamethoxazole versus minocycline monotherapy for Stenotrophomonas maltophilia pneumonia.

METHODS

A single-centre, retrospective cohort study of patients with S. maltophilia pneumonia admitted 1 March 2018-30 September 2023 was conducted comparing treatment with trimethoprim-sulfamethoxazole versus minocycline monotherapy. The primary outcome was the rate of clinical cure, defined as meeting two of the three prespecified criteria for a period of 48 hours while on definitive therapy: normalization of white blood cell count, absence of fever and hypothermia and decreased oxygen support. Secondary outcomes evaluated included time to clinical cure, infection-related and in-hospital mortality, pneumonia recurrence and incidence of adverse effects, which was a composite of acute kidney injury (AKI), hyperkalaemia and thrombocytopenia.

RESULTS

Of 93 patients included, 48 received trimethoprim-sulfamethoxazole and 45 received minocycline. There was no difference in the primary outcome of clinical cure between the trimethoprim-sulfamethoxazole and minocycline groups (72.9% versus 66.7%, P = 0.51). S. maltophilia pneumonia recurrence was more common in the minocycline group compared to the trimethoprim-sulfamethoxazole group (35.6% versus 10.4%, P = 0.006). In-hospital mortality was higher in the trimethoprim-sulfamethoxazole group although there was no difference in infection-related in-hospital mortality (6.3% versus 2.3%, P = 0.62). The incidence of AKI, hyperkalaemia and thrombocytopenia did not differ between groups.

CONCLUSION

There was no difference in clinical cure rate for S. maltophilia pneumonia treatment between trimethoprim-sulfamethoxazole and minocycline monotherapy although higher rates of recurrent pneumonia were observed in patients treated with minocycline. Rates of adverse effects were similar between groups.

Role of respiratory secretion culture in the surgical outcome prediction of bacterial empyema

OBJECTIVES

Thoracic empyema is a serious infection. Video-assisted thoracoscopic surgery is a recommended treatment, and pleural fluid and tissue cultures are collected intraoperatively. The combination of a pleural peels tissue culture and a pleural fluid culture improves the positive culture rate. We aimed to investigate the role of respiratory secretion cultures to determine the optimal management for improving surgical outcome.

METHODS

The study analyzed 225 adult patients with phase II/III thoracic empyema who underwent thoracoscopic decortication. Respiratory secretion cultures were obtained and compared with pleural cultures. Key outcomes were culture positivity and pathogen consistency, with secondary outcomes including intensive care unit stay, hospital stay, and mortality.

RESULTS

There were 225 empyema patients with either a positive pleural fluid culture or a positive pleural peel tissue culture. Of these, 76 patients had positive respiratory secretion culture findings during hospitalization. The most common pathogen species were Pseudomonas aeruginosa (44%) and Klebsiella pneumoniae (16%) in the respiratory secretion cultures and Streptococcus spp. (38%) and Klebsiella pneumoniae (12%) in the pleural cultures. There were 30 patients having a common pathogen in the respiratory secretion culture and in the pleural fluid/tissue culture. Poor outcome measures were found in these patients, including the longer use of antibiotics preoperatively [2.50 (1.00-6.00) days versus 5.00 (2.75-11.00) days, p = 0.006] and a higher mortality rate during hospitalization (40.0% versus 17.4%, p = 0.002).

CONCLUSIONS

Respiratory secretion cultures are vital for predicting surgical outcomes in bacterial empyema, and prompt specimen collection can improve patient survival.

Real-world study on disease burden and current clinical practice of hospital-acquired pneumonia in Japan

BACKGROUND

Hospital-acquired pneumonia (HAP) is a common nosocomial infection and is associated with high mortality. Despite advances in the understanding of the causes and prevention of HAP, it continues to be a frequent complication associated with hospital care. Presently, there are no large retrospective cohort studies on HAP in Japan.

METHODS

A retrospective cohort study was conducted using the Medical Data Vision Co. Ltd. database for the study period (April 1, 2015 to May 31, 2018). The study population was defined based on ICD-10 codes for bacterial pneumonia, characteristics of hospitalization, and prescription of injection-only antibiotics. The study included patients ≥18 years of age with at least one episode of HAP during the identification period, where the episode was defined as hospitalization with HAP within the study identification period.

RESULTS

A total of 2968 patients were included in this study contributing to 2979 HAP episodes. Patients with HAP were more likely to be male (64.9 %) and older than age 65 (86.5 %). The top three frequently prescribed antibiotics were sulbactam-ampicillin (39.7 %; 1183 episodes), tazobactam-piperacillin (28.4 %; 846 episodes) and ceftriaxone (23.2 %; 690 episodes). The mean (±SD) length of hospital stay during overall hospitalization and the HAP period were 49.9 (±34.2) days and 11.3 ± 7.3 days respectively. The HAP patient mortality at discharge was 22.0 %.

CONCLUSION

The present study provided insights regarding the characteristics, treatment patterns of HAP patients in Japan. Further, the study provided noteworthy information regarding antibiotic usage trends in the aging Japanese population.

Antibiotic duration for common bacterial infections-a systematic review

Background

Reducing antibiotic duration is a key stewardship intervention to mitigate antimicrobial resistance (AMR). We examined current evidence informing antibiotic duration for common bacterial infections to identify any gaps in terms of settings, patient populations and infectious conditions. Trial methodologies were assessed to identify areas for improvement.

Methods

MEDLINE and Embase were searched up to July 2024 for randomized trials comparing antibiotic durations in hospital and community settings (PROSPERO 2021, CRD42021276209). A narrative synthesis of the results was performed with a review on the major guidelines published by IDSA, NICE, WHO and other international societies to assess the impact of these trials on practice guidance.

Results

Out of 315 studies, 85% concluded equivalence or non-inferiority of shorter courses. Adult bacterial sinusitis, community-acquired pneumonia, female cystitis/pyelonephritis, uncomplicated cellulitis and intra-abdominal infection with adequate source control and perioperative prophylaxis had robust evidence supporting shorter durations. Few trials studied severe infections, such as bloodstream infections and ventilator-associated pneumonia. Twenty-three (7%) of the trials were conducted in intensive care settings and only 43 trials (14%) enrolled patients from low-to-middle- or low-income countries. Only 15% of studies were at low risk for bias.

Conclusions

Reducing antibiotic duration likely remains an important strategy for antibiotic stewardship, and an area of active research. While shorter antibiotic courses may be suitable for many bacterial infections, more evidence is needed for severe infections and in low- and middle-income settings.

Effects of early supplemental parenteral nutrition on new-onset infection in adults with acute severe stroke: a single-center retrospective case-control study

BACKGROUND

Early adequate feeding reduces mortality in patients with acute severe stroke. Supplemental parenteral nutrition (SPN) may address enteral nutrition (EN) deficiency and mitigate the risk of nosocomial infection. The benefit of the EN plus early SPN strategy over the full EN strategy is unknown in acute severe stroke patients.

METHODS

We retrospectively enrolled 20 patients with acute severe stroke in the SPN group who received EN plus early SPN (more than 50% of the energy target within 72 h after admission). Forty control patients in the EN group who received full EN were matched by age, sex and lesion site. The time to new-onset pneumonia or nosocomial infections was analyzed by Student's t test and the Breslow generalized Wilcoxon test.

RESULTS

The baseline characteristics did not differ significantly between the SPN group and the EN group, except for higher serum leukocyte counts, neutrophil counts, and neutrophil-to-lymphocyte ratios in the SPN group (P < 0.05). Compared with that in the EN group, the time to new-onset pneumonia was significantly delayed in the SPN group (7.6 days vs. 5.2 days; mean difference, 2.5 days; 95% CI, 0.65 to 4.31; P = 0.009), as was the time to new-onset nosocomial infections (7.1 days vs. 4.8 days; mean difference, 2.3 days; 95% CI, 0.46 to 4.07; P = 0.015). Kaplan-Meier analysis revealed similar cumulative probabilities of new-onset pneumonia and new-onset nosocomial infections in the two groups (P > 0.05). The rates of digestive intolerance events were similar between the two groups (40% in the SPN group vs. 52.5% in the EN group, P = 0.361).

CONCLUSIONS

In patients with acute severe stroke, the application of EN plus early SPN could delay the onset of pneumonia and nosocomial infections especially in the early phase.

Detection rate of herpes simplex virus DNA in the lower respiratory tract of critical care patients with or without coinfection determined by the Biofire® pneumonia plus panel

We investigated whether the results returned by the Biofire® Pneumonia Plus Panel (FA-PP) in lower respiratory tract specimens (LRT) specimens may identify patients who should be targeted for Herpes simplex virus (HSV) DNA testing. We included 35 adult ICU patients who underwent protocolized HSV DNA testing in LRT and/or plasma specimens by real-time PCR. Of these, one patient underwent allogeneic hematopoietic cell transplantation, one a kidney transplantation and one was under CAR-T cell therapy. Twenty-three of the 33 patients (69.6 %) had HSV-type 1 (HSV-1) DNA detected in LRT specimens (median viral load: 5.67 log10 copies/ml). Viral DNA was detected in 12/14 (85 %) plasma samples (median, 3.4 log10 copies/ml) from patients with HSV-1 DNA present in LRT specimens. Patients testing positive by the FA-PP had a non-significant (P = 0.28) higher rate of HSV-1 DNA detection (10/13; 77 %) compared with patients returning negative results (9/16; 56 %). In conclusion, requests for HSV DNA testing in ICU patients should not depend on the results of conventional culture methods nor those provided by the FA-PP.

Moxifloxacin-Loaded Polymeric Nanoparticles for Overcoming Multidrug Resistance in Chronic Pulmonary Infections Caused by Pseudomonas aeruginosa

Pseudomonas aeruginosa (P. aeruginosa) infections are increasingly challenging due to their propensity to form biofilms and low outer membrane permeability, especially in chronically infected patients with thick mucus. P. aeruginosa exhibits multiple drug resistance mechanisms, making it one of the most significant global public health threats. In this study, we found that moxifloxacin (MXC) and antibacterial peptides (ε-poly-l-lysine, ε-PLL) exhibited a synergistic effect against multidrug-resistant P. aeruginosa (MDR-P. aeruginosa). MXC was combined with ε-PLL to prepare lipase-responsive nanoparticles (MCIP/(PEG-PCL)/PLL NPs) with a weakly negative charge. The weakly negatively charged MCIP/(PEG-PCL)/PLL NPs demonstrated remarkable mucus and biofilm penetration capabilities, thereby overcoming one of the adaptive drug resistance mechanisms. MCIP/(PEG-PCL)/PLL NPs improved the outer and inner membrane permeability and inhibited the expression of the efflux pump MexAB-OprM gene in MDR-P. aeruginosa, thereby overcoming mechanisms of both intrinsic and acquired drug resistance. Meanwhile, the nanoparticles demonstrated an ability to reduce repeated infections with MDR-P. aeruginosa. Additionally, the bacterial burden in the lungs of mice treated with MCIP/(PEG-PCL)/PLL NPs was significantly lower than that in the MXC group, resulting in a 99% clearance rate. Notably, MCIP/(PEG-PCL)/PLL NPs showed no toxicity toward BEAS-2B cells or RAW 267.4 cells, nor did they adversely affect pulmonary function or major organs. This study demonstrated the potential of the nanodrug delivery system composed of the antibiotic moxifloxacin and the antibacterial peptide ε-PLL in addressing the clinical challenges of treating chronic pulmonary infections caused by MDR-P. aeruginosa.

Modeling and simulation of distribution and drug resistance of major pathogens in patients with respiratory system infections

BACKGROUND

Respiratory tract infections (RTIs) are one of the leading causes of morbidity and mortality worldwide. The increase in antimicrobial resistance in respiratory pathogens poses a major challenge to the effective management of these infections.

OBJECTIVE

To investigate the distribution of major pathogens of RTIs and their antimicrobial resistance patterns in a tertiary care hospital and to develop a mathematical model to explore the relationship between pathogen distribution and antimicrobial resistance.

METHODS

Five hundred patients with RTIs were included in the study and 475 bacterial strains were isolated from their respiratory specimens. Antimicrobial susceptibility testing and analysis of influencing factors were performed. A mathematical model was developed to simulate the relationship between pathogen distribution and drug resistance.

RESULTS

The most common pathogens were Streptococcus pneumoniae (30%), Haemophilus influenzae (20%), Pseudomonas aeruginosa (15%), Staphylococcus aureus (10%) and Klebsiella pneumoniae (10%). The distribution of pathogens varied according to age group and type of RTIs, with higher proportions of Pseudomonas aeruginosa and Staphylococcus aureus in hospital-acquired and ventilator-associated pneumonia. Isolated pathogens showed high and increasing rates of resistance to commonly used antibiotics. Model simulations suggest that a shift in the distribution of pathogens toward more resistant strains may lead to a significant increase in overall resistance rates, even if antibiotic use patterns remain unchanged.

CONCLUSION

This study emphasizes the importance of regular monitoring of respiratory pathogen distribution and antimicrobial resistance patterns and the need for a comprehensive approach to managing RTIs, including implementation of antibiotic stewardship programs, infection control measures, and development of new therapies.

[Pneumonia and pregnancy]

Acute community-acquired pneumonia (CAP) during pregnancy is a frequently encountered and potentially severe condition. CAP incidence and ecology are unchanged during pregnancy as compared with the overall young adult population. Risk factors specifically identified in pregnant women include advanced gestational age, asthma, anemia and repeated courses of corticosteroid therapy for fetal lung maturation. The clinical presentation of CAP is not altered during pregnancy. Key points in the pregnant host encompass: (i) reduced maternal tolerance to hypoxia, due to physiological adaptations during pregnancy; (ii) heightened severity of some infections, notably viral pneumonias such as influenza, varicella or SARS-CoV-2 pneumonia; (iii) potentially deleterious fetal repercussions of infection and maternal hypoxia, with an increased risk of premature delivery and prematurity; (iv) the need for specific attention to the risk of fetal irradiation in the performance of possibly repeated radiological examinations and (v) therapeutic specificities arising from the possible embryo-fetal toxicity of certain anti-infectious agents. CAP prevention is premised on compliance with universal hygiene measures and on vaccination, which guarantees protection against severe forms of pneumonia not only in the mother (Streptococcus pneumoniae, seasonal flu, chickenpox, COVID-19), but also in the child during the first few months of life (whooping cough, RSV).

Activity of Aztreonam-avibactam and other β-lactamase inhibitor combinations against Gram-negative bacteria isolated from patients hospitalized with pneumonia in United States medical centers (2020-2022)

BACKGROUND

Initial antimicrobial therapy for pneumonia is frequently empirical and resistance to antimicrobial agents represents a great challenge to the treatment of patients hospitalized with pneumonia. We evaluated the frequency and antimicrobial susceptibility of Gram-negative bacteria causing pneumonia in US hospitals.

METHODS

Bacterial isolates were consecutively collected (1/patient) from patients hospitalized with pneumonia and the susceptibility of Gram-negative bacilli (3,911 Enterobacterales and 2,753 non-fermenters) was evaluated by broth microdilution in a monitoring laboratory. Isolates were collected in 69 medical centers in 2020-2022. Aztreonam-avibactam was tested with avibactam at fixed 4 mg/L and a pharmacokinetic/pharmacodynamic susceptible (S) breakpoint of ≤ 8 mg/L was applied for comparison. Carbapenem-resistant Enterobacterales (CRE; isolates with MIC values of > 2 mg/L for imipenem and/or meropenem) isolates were screened for carbapenemases by whole genome sequencing.

RESULTS

Gram-negative bacilli represented 71.1% of organisms. The most common Gram-negative species were Pseudomonas aeruginosa (22.4% of organisms), Klebsiella pneumoniae (8.8%), Escherichia coli (6.6%), Serratia marcescens (6.2%), Stenotrophomonas maltophilia (4.9%), and Enterobacter cloacae complex (4.8%). Aztreonam-avibactam inhibited 100.0% of Enterobacterales at ≤ 8 mg/L and 99.9% at ≤ 4 mg/L and showed potent activity against CRE (MIC50/90, 0.25/1 mg/L). Ceftazidime-avibactam and meropenem-vaborbactam were active against 89.4% and 88.5% of CREs, respectively. Aztreonam-avibactam retained activity against Enterobacterales non-susceptible to ceftazidime-avibactam and/or meropenem-vaborbactam (n = 19; MIC50/90, 0.25/4 mg/L). The most common carbapenemases were KPC (69.2% of CREs), NDM (9.6%), and SME (4.8%). A carbapenemase gene was not identified in 16.3% of CREs. Ceftazidime-avibactam and meropenem-vaborbactam were highly active against KPC and SME producers but showed limited activity against MBL producers. The most active comparators against CRE were tigecycline (95.2%S), amikacin (73.1%S), and gentamicin (60.6%S). Among Pseudomonas aeruginosa, 79.1% were inhibited at ≤ 8 mg/L of aztreonam-avibactam, 77.2% were meropenem susceptible, and 77.2% were piperacillin-tazobactam susceptible. Aztreonam-avibactam was highly active against S. maltophilia, inhibiting 99.5% of isolates at ≤ 8 mg/L.

CONCLUSIONS

Aztreonam-avibactam displayed potent in vitro activity against a large collection of contemporary Gram-negative organisms isolated from patients hospitalized with pneumonia, including CRE isolates resistant to ceftazidime-avibactam and/or meropenem-vaborbactam. Results of surveillance programs are valuable for planning empiric antimicrobial therapy guidelines and infection control measures.

Targeted Next-Generation Sequencing in Pneumonia: Applications in the Detection of Responsible Pathogens, Antimicrobial Resistance, and Virulence

Background

Targeted next-generation sequencing (tNGS) is a high-throughput and cost-effective diagnostic alternative for pneumonia, with the ability to simultaneously detect pathogens, antimicrobial resistance genes, and virulence genes. We aimed to explore the applicability of tNGS in the co-detection of the responsible pathogens, antimicrobial resistance (AMR) genes, and virulence genes in patients with pneumonia.

Methods

A prospective study was conducted among patients with suspected pneumonia at Ruijin Hospital from March 1 to May 31, 2023. Bronchoalveolar lavage fluid (BALF) or sputum samples were collected and sent for tNGS, metagenomic next-generation sequencing (mNGS), and conventional microbiological tests (CMTs).

Results

In total, 67 BALF and 11 sputum samples from 78 patients were included in the analyses. According to the composite reference standards, the accuracy of tNGS in the detection of responsible pathogens was 0.852 (95% confidence interval 0.786-0.918), which resembled that of mNGS and remarkably exceeded that of CMTs. In addition, 81 AMR genes associated with responsible pathogens were reported, and 75.8% (25/33) priority drug-resistant pathogens could be directly identified. A total of 144 virulence genes were detected for four common pathogens. And patients with virulence genes detected were of higher proportions of severe pneumonia (95.0% vs 42.9%, P = 0.009), acute respiratory distress syndrome (55.0% vs 0%, P = 0.022), and neutrophils (82.3% vs 62.2%, P = 0.026) than those not.

Conclusion

In patients with pneumonia, tNGS could detect the responsible pathogens, AMR genes, and virulence genes simultaneously, serving as an efficient and cost-effective tool for the diagnosis, treatment, and severity indication of pneumonia.

Etiology of Hospital-Acquired Pneumonia (HAP) and Ventilator-Associated Pneumonia (VAP) in Tertiary-Care Hospitals in Thailand: A Multicenter, Retrospective Cohort Study

Purpose

To describe the top three causative organisms of hospital acquired pneumonia (HAP) and ventilator-associated pneumonia (VAP) in Thailand.

Patients and Methods

This multi-center retrospective cohort study included HAP/VAP patients hospitalized in 2019 in three university-affiliated hospitals and a private hospital in Bangkok, Thailand. Medical records of patients with a documented diagnosis of nosocomial pneumonia (NP) were systematically reviewed to collect data on demographic, clinical, microbiological, and 30-day readmission due to NP.

Results

A total of 240 patients were included in the study, comprises patients with VAP (62.9%), HAP (36.7%), and ventilated HAP (vHAP) (0.4%). All of the patients had late-onset NP, occurring after five days of hospitalization with median time to NP of 13 days (interquartile range [IQR] 6-25 days) from admission. The top three causative pathogens of NP were Acinetobacter baumannii (44.2%), Pseudomonas aeruginosa (34.6%), and Klebsiella pneumoniae (28.3%). A high rate of carbapenem resistance (CR) in A. baumannii (92.5%) was observed. Lower rates of CR were observed in K. pneumoniae (20.6%) and P. aeruginosa isolates (16.9%). Readmission rate due to NP within 30 days after discharge was less than 2% with median time of 4 days (IQR 3-20 days) after discharge. After diagnosis of NP, 19 patients were transferred to intensive care units with median length of stays of 11 days (IQR 3-24 days). Fifty-one percent of HAP patients received mechanical ventilation support after the diagnosis of NP with median length of mechanical ventilation use of 12 days (IQR 6-22 days).

Conclusion

A. baumannii, with its significant carbapenem resistance, presents a major HAP/VAP pathogens and imposes a substantial burden on healthcare resources in this study. Implementation of regular surveillance for causative organisms of NP and their susceptibility profiles are critical for the success of HAP/VAP management, and reducing the related burden of healthcare resources.

Utilizing Targeted Next-Generation Sequencing for Rapid, Accurate, and Cost-Effective Pathogen Detection in Lower Respiratory Tract Infections

Objective

To evaluate the diagnostic performance and clinical impact of targeted next-generation sequencing (tNGS) in patients with suspected lower respiratory tract infections.

Methods

Following propensity score matching, we compared the diagnostic performances of tNGS and metagenomic next-generation sequencing (mNGS). Furthermore, the diagnostic performance of tNGS was compared with that of culture, and its clinical impact was assessed.

Results

After propensity score matching, the coincidence rate of tNGS was comparable to that of mNGS (82.9% vs 73.9%, P=0.079). The detection rates for bacterial, viral, fungal, and mixed infections were not significantly different (P>0.05). Bacterial-viral co-infection (16.7%) was the most common mixed infection detected by tNGS. tNGS showed a higher detection rate than culture (75.2% vs 19.0%, P<0.01). The positive detection rate by tNGS was not significantly different between immunocompromised and immunocompetent patients (88.6% vs 80.5%, P=0.202), but was significantly higher than that by culture (P<0.001). Moreover, 65 patients (44.5%) had their medications modified based on the tNGS results, and the majority exhibited notable improvement regardless of treatment adjustment.

Conclusion

tNGS performs comparably to mNGS and surpasses culture in detecting lower respiratory tract infections. Nevertheless, tNGS is faster and more cost-effective than mNGS, making it highly significant for guiding rational treatment.

Comparison of Multi-Drug Resistant Organisms Causing Early Ventilator-Associated Pneumonia in Three Geographically Distinct Trauma Intensive Care Units

Introduction: It is unclear why differences in patient location change organisms causing ventilator-associated pneumonia (VAP). We investigated VAP organisms in three geographically separate trauma intensive care units (TICUs). Patients and Methods: A retrospective review of organisms causing VAP (bronchoalveolar lavage [BAL] performed ≤7 d after admission and growing ≥105 cfu/mL) in three geographically separate TICUs was conducted. Patients were treated by similar multidisciplinary teams and protocolized pathways. The primary outcome was the incidence of multi-drug resistant (MDR) VAP. Secondary outcomes were the incidence of inappropriate empiric antimicrobial therapy (IEAT) and the determination of risk factors for MDR VAP. Chi-squared, Kruskal-Wallis, and multi-variable logistic regression analyses were used accordingly. Results: In total, 271 patients were included: 142 in TICU-1, 63 in TICU-2, and 66 in TICU-3. The incidence of MDR VAP was similar across TICUs at 33.8%, 47.6%, and 39.4%, respectively (p = 0.17). Gram-negative MDRs were more prevalent in TICU-1 (70.8%) versus TICU-2 (60.0%) or TICU-3 (26.9%) (p = 0.001). Gram-positive MDRs were identified more in TICU-3 (73.1%) versus TICU-2 (43.3%) or TICU-1 (35.4%). IEAT did not differ by unit overall but was significantly greater for MDR gram-positive organisms in TICU-3 (70.4%) versus TICU-2 (44.8%) or TICU-1 (37.5%) (p = 0.02) and highest for MDR gram-negative organisms in TICU-1 (64.6%) versus TICU-2 (62.1%) or TICU-3 (55.8%) (p = 0.02). Multi-variable regression analyses revealed antibiotic days before BAL and kidney replacement therapy (KRT) as significant predictors of MDR VAP. Conclusions: Different TICU locations did not influence the overall incidence of MDR VAP, but differences in MDR organisms were observed. IEAT rates for both gram-positive and gram-negative organisms in different units may necessitate changes in empiric therapy. Antibiotic days prior to the BAL and KRT significantly increased the odds of early MDR VAP.

Diagnostic Approach to Pneumonia in Immunocompromised Hosts

In immunocompromised patients, pneumonia presents a diagnostic challenge due to diverse etiologies, nonspecific symptoms, overlapping radiological presentation, frequent co-infections, and the potential for rapid progression to severe disease. Thus, timely and accurate diagnosis of all pathogens is crucial. This narrative review explores the latest advancements in microbiological diagnostic techniques for pneumonia in immunocompromised patients. It covers major available microbiological tools for diagnosing both community-acquired and hospital-acquired pneumonia, encompassing a wide spectrum of pathogens including bacterial, viral, fungal, and parasitic. While traditional culture methods remain pivotal in identifying many pneumonia-causing etiologies, their limitations in sensitivity and time to results have led to the rise of non-invasive antigen tests and molecular diagnostics. These are increasingly employed alongside cultures and microscopy for more efficient diagnosis, mainly in viral and fungal infections. Lastly, we report the future of pneumonia diagnostics, exploring the potential of metagenomics and CRISPR/Cas13a for more precise and rapid pathogen detection in immunocompromised populations.

Comparison of the Impact of tNGS with mNGS on Antimicrobial Management in Patients with LRTIs: A Multicenter Retrospective Cohort Study

Background

tNGS and mNGS are valuable tools for diagnosing pathogens in lower respiratory tract infections (LRTIs), which subsequently influence treatment strategies. However, the impact of tNGS and mNGS on antimicrobial stewardship in patients with LRTIs remains unclear.

Methods

Patients diagnosed with LRTIs who underwent tNGS or mNGS between June 2021 and January 2024 were included. Patients who underwent both tNGS and conventional microbiologic tests (CMTs) were grouped into the tNGS group, the others were divided into the mNGS group. Then, the diagnostic efficacy of tNGS and mNGS was compared, along with their impact on antimicrobial management and clinical outcomes.

Results

548 patients with an initial diagnosis of LRTIs who underwent tNGS or mNGS were evaluated. Finally, 321 patients were analyzed, with 117 patients in tNGS group and 204 patients in mNGS group. The overall pathogen detection rates for tNGS and mNGS were 89.74% and 89.71% (P=0.991). The distribution of detected pathogens was similar between tNGS and mNGS, with bacteria being the predominant microorganisms. The proportions of patients who underwent antimicrobial agent changes and received targeted therapy were not significantly different between tNGS and mNGS groups (P=0.270; P=0.893). Additionally, no significant differences were noted in the rates of antibiotic de-escalation, escalation, or changes in the opposite direction (all P>0.05). The same results was observed in the proportions of patients with addition or reductions in antiviral, antifungal, and antibacterial agents (all P>0.05). Hospital stays, improvement rate and mortality rate were also similar (all P>0.05).

Conclusion

tNGS and mNGS demonstrate comparable overall pathogen yield rates in patients with LRTIs. Furthermore, tNGS is also comparable to mNGS in terms of adjusting antimicrobial treatments and clinical outcomes, tNGS meets the clinical needs of most patients with LRTIs and can be firstly used for these patients.

Ventilator-Associated Pneumonia After Cardiac Arrest and Prevention Strategies: A Narrative Review

Background and Objectives: Ventilator-associated pneumonia (VAP) poses a significant threat to the clinical outcomes and hospital stays of mechanically ventilated patients, particularly those recovering from cardiac arrest. Given the already elevated mortality rates in cardiac arrest cases, the addition of VAP further diminishes the chances of survival. Consequently, a paramount focus on VAP prevention becomes imperative. This review endeavors to comprehensively delve into the nuances of VAP, specifically in patients requiring mechanical ventilation in post-cardiac arrest care. The overarching objectives encompass (I) exploring the etiology, risk factors, and pathophysiology of VAP, (II) delving into available diagnostic modalities, and (III) providing insights into the management options and recent treatment guidelines. Methods: A literature search was conducted using PubMed, MEDLINE, and Google Scholar databases for articles about VAP and Cardiac arrest. We used the MeSH terms "VAP", "Cardiac arrest", "postcardiac arrest syndrome", and "postcardiac arrest syndrome". The clinical presentation, diagnostic, and management strategies of VAP were summarized, and all authors reviewed the selection and decided which studies to include. Key Content and Findings: The incidence and mortality rates of VAP exhibit significant variability, yet a recurring pattern emerges, marked by prolonged hospitalization and exacerbated clinical outcomes. This pattern is attributed to the elevated incidence of drug-resistant infections and the delayed initiation of antimicrobial treatment. This review focuses on VAP, aiming to offer valuable insights into the efficient identification and management of this fatal complication in post-cardiac arrest patients. Conclusion: The prognosis for survival after cardiac arrest is already challenging, and the outlook becomes even more daunting when complicated by VAP. The timely diagnosis of VAP and initiation of antibiotics pose considerable challenges, primarily due to the invasive nature of obtaining high-quality samples and the time required for speciation and identification of antimicrobial sensitivity. The controversy surrounding prophylactic antibiotics persists, but promising new strategies have been proposed; however, they are still awaiting well-designed clinical trials.

Impact of Multidrug-Resistant Bacterial Colonization on Clinical Characteristics, Antibiotic Treatment, and Clinical Outcomes of Hospital-Acquired Pneumonia

PURPOSE

To determine effects of colonization with multidrug-resistant bacteria (MDRB) in general wards on characteristics, treatment, and prognosis of hospital-acquired pneumonia (HAP).

METHODS

This was a multicenter retrospective cohort study of patients with HAP admitted to 16 tertiary or university hospitals in Korea from July 2019 to December 2019. From the entire cohort, patients who developed pneumonia in general wards with known colonization status before the onset of pneumonia were included in this study. Patients were categorized into a colonization group and a non-colonization group according to MDRB colonization. Patients of the two groups were then compared.

RESULTS

Among a total of 400 patients, 63 were in the MDRB colonization group. HAP caused by MDR-Staphylococcus aureus or MDR-Pseudomonas aeruginosa was more common in the colonization group than in the non-colonization group (24.4% vs. 8.1%, P = 0.006 or 20.0% vs. 5.4%, P = 0.013, respectively). Colonization with certain bacteria was correlated with subsequent infection with the same bacteria. Carbapenem use (36.5% vs. 24.3%, P = 0.044) and appropriateness of initial antibiotics (50.8% vs. 12.8%) were higher in the colonization group than in the non-colonization group. Although in-hospital mortality was similar in the two groups (34.9% vs. 32.9%, P = 0.759), hospital length of stay was longer (38 days vs. 31 days, P = 0.009) and rate of discharge to home was lower (34.1% vs 59.7%, P = 0.002) in the colonization group.

CONCLUSIONS

Colonization with MDRB might influence characteristics and treatment of HAP. However, prognosis of HAP was not associated with MDRB colonization.

Mechanical Ventilator-Associated Pneumonia in the COVID-19 Pandemic Era: A Critical Challenge in the Intensive Care Units

Background/Objectives: Ventilator-associated pneumonia (VAP) is the most common nosocomial infection encountered in the intensive care unit (ICU) and is associated with prolonged hospitalization and increased mortality. We evaluated the causative pathogens involved and their resistance to the major classes of antibiotics in patients with VAP and assessed the differences between patients with and without coronavirus disease 2019 (COVID-19). Materials and Methods: This study was a single-center, cross-sectional, retrospective analysis involving 122 patients who were hospitalized in the ICU of Târgu Mureș County Clinical Hospital from 1 April 2021, to 1 April 2023. This study compares patients with VAP in COVID-19 and non-COVID-19 groups, examining the clinical progression, duration of ventilation and hospitalization, mortality, pathogen distribution, and the emergence of multidrug-resistant strains. Results: A length of stay in the ICU exceeding 11.5 days was associated with the development of multidrug-resistant (MDR) infections (AUC: 0.708, p < 0.001). Similarly, a duration of MV exceeding 196 h was associated with MDR acquisition (AUC: 0.695, p = 0.002). Additionally, a Clinical Pulmonary Infection Score (CPIS) greater than 5 was associated with MDR development (AUC: 0.854, p < 0.001) in the whole group of patients. The most commonly isolated strains were Acinetobacter spp., Pseudomonas spp., Klebsiella spp., and Staphylococcus aureus. Among non-COVID-19 patients, there was a notably higher frequency of MDR Acinetobacter baumannii. A bacterial resistance to carbapenems was found in Acinetobacter spp. (51.6%), Klebsiella spp. (22.6%), and Pseudomonas spp. (25.8%). Conclusions: COVID-19 patients experienced longer ventilation, higher mortality, and an increased risk of developing MDR. Carbapenem resistance was universal in Acinetobacter spp. and Klebsiella pneumoniae, whereas resistance in Pseudomonas aeruginosa was more prevalent among non-COVID-19 patients. The Clinical Pulmonary Infection Score (CPIS) strongly correlates with developing MDR pathogens in both patient groups.

Effects of Candida colonization on patients with ventilator-associated pneumonia and pathogenic microorganisms: Systematic review and meta-analysis

BACKGROUND

In the intensive care unit (ICU), patients undergoing mechanical ventilation (MV) often exhibit Candida colonization. This study aims to systematically review and analyze the effects of Candida colonization on the outcomes of mechanically ventilated patients and its relationship with bacterial pathogens associated with ventilator-associated pneumonia (VAP).

METHODS

We conducted a comprehensive search across PubMed, Embase, Web of Science (WOS), and the Cochrane Central Register of Controlled Trials (CENTRAL) without language restrictions to identify eligible studies. Inclusion criteria involved patients undergoing MV for >2 days, encompassing those with clinically suspected VAP (csVAP), and confirmed VAP patients. We assessed the impact of Candida colonization on patient prognosis, length of ICU stay, bacterial pathogens responsible for VAP, and inflammatory markers. The study protocol was registered with PROSPER (CRD42024580547).

RESULTS

Thirteen studies involving 3,802 patients were included in our analysis. The prevalence of Candida colonization among MV patients ranged from 10 % to 56 %. Our findings indicated that Candida airway colonization was associated with poorer patient prognosis (95 % CI 1.13-1.52, p < 0.05, I² = 39 %). Among patients who developed VAP, Candida colonization correlated with increased detection rates of Pseudomonas aeruginosa (RR = 1.37, 95 % CI 1.07-1.75, p = 0.01, I² = 3 %) and Acinetobacter baumannii (RR= 1.48, 95 % CI 1.17-1.86, p < 0.01, I² = 27 %). Additionally, an association with antibiotic resistance was observed, although the quality of evidence was low. In studies that recorded patients' inflammatory markers, no significant effect of Candida colonization on inflammatory markers (procalcitonin, interleukin-6) was observed.

CONCLUSION

Candida airway colonization is highly prevalent among mechanically ventilated patients and should be considered a marker of poor prognosis when it occurs. Antibiotics should be used more carefully when Candida colonization is detected in the respiratory tract of mechanically ventilated patients.

Antibiotic Length of Therapy: Is Shorter Better in Older Adults?

Background Antibiotic lengths of therapy (LOT) vary widely, based on infection type, antibiotic regimen, and patient characteristics. Longer LOT are associated with increased risk of antibiotic resistance, adverse effects, and health care costs. There are increasing data supporting shorter LOT for many infections based on randomized, controlled trials (RCTs). Objective To evaluate RCTs supporting shorter antibiotic LOT for common infections, with an emphasis on applying the data to older adults. Data Sources A list of RCTs that evaluated shorter LOT for common infections was first gathered from the website of Brad Spellberg, MD, at https://www.bradspellberg.com/shorter-is-better. The list was then verified through a PubMed search using the terms for each infection and LOT. Data Synthesis Of the 28 identified RCTs, 27 supported shorter antibiotic LOT. These trials were categorized by disease states: complicated urinary tract infections including pyelonephritis (n = 9), community-acquired pneumonia (n = 6), hospital-acquired pneumonia/ ventilator-associated pneumonia (n = 3), skin and soft tissue infections (n = 4), complicated intra-abdominal infections (n = 2), and gram-negative bacteremia (n = 3). The single incongruent trial was conducted on male patients with complicated urinary tract infections, and the results could be explained by a lower than usual dose of antibiotic utilized in the study. Discussion Many RCTs have demonstrated the safety and efficacy of shorter antibiotic LOT for the disease states included in this review. Several of these trials enrolled older adults. Conclusion There are sufficient data to support using shorter antibiotic LOT in older patients. Implementing this strategy can help pharmacists and other health care professionals optimize antibiotic use in older adults.

The evidence base for the optimal antibiotic treatment duration of upper and lower respiratory tract infections: an umbrella review

BACKGROUND

Many trials, reviews, and meta-analyses have been performed on the comparison of short versus long antibiotic treatment in respiratory tract infections, generally supporting shorter treatment. The aim of this umbrella review is to assess the soundness of the current evidence base for optimal antibiotic treatment duration.

METHODS

A search in Ovid MEDLINE, Embase, and Clarivate Analytics Web of Science Core Collection was performed on May 1, 2024, without date and language restrictions. Systematic reviews addressing treatment durations in community-acquired pneumonia (CAP), acute exacerbation of chronic obstructive pulmonary disease (AECOPD), hospital-acquired pneumonia (HAP), acute sinusitis, and streptococcal pharyngitis, tonsillitis, or pharyngotonsillitis were included. Studies from inpatient and outpatient settings were included; reviews in paediatric populations were excluded. Outcomes of interest were clinical and bacteriological cure, microbiological eradication, mortality, relapse rate, and adverse events. The quality of the reviews was assessed using the AMSTAR 2 tool, risk of bias of all included randomised controlled trials (RCTs) using the Cochrane risk-of-bias tool (version 1), and overall quality of evidence according to GRADE.

FINDINGS

We identified 30 systematic reviews meeting the criteria; they were generally of a low to critically low quality. 21 reviews conducted a meta-analysis. For CAP outside the intensive care unit (ICU; 14 reviews, of which eight did a meta-analysis) and AECOPD (eight reviews, of which five did a meta-analysis), there was sufficient evidence supporting a treatment duration of 5 days; evidence for shorter durations is scarce. Evidence on non-ventilator-associated HAP is absent, despite identifying three reviews (of which one did a meta-analysis), since no trials were conducted exclusively in this population. For sinusitis the evidence appears to support a shorter regimen, but more evidence is needed in the population who actually require antibiotic treatment. For pharyngotonsillitis (eight reviews, of which six did a meta-analysis), sufficient evidence exists to support short-course cephalosporin but not short-course penicillin when dosed three times a day.

INTERPRETATION

The available evidence for non-ICU CAP and AECOPD supports a short-course treatment duration of 5 days in patients who have clinically improved. Efforts of the scientific community should be directed at implementing this evidence in daily practice. High-quality RCTs are needed to underpin even shorter treatment durations for CAP and AECOPD, to establish the optimal treatment duration of HAP and acute sinusitis, and to evaluate shorter duration using an optimal penicillin dosing schedule in patients with pharyngotonsillitis.

FUNDING

None.

Pharmacokinetics of vancomycin in sputum of intubated patients: Optimized intravenous delivery vs. inhaled therapy

AIMS

Intubated patients with methicillin-resistant Staphylococcus aureus pneumonia, fail optimized treatment with intravenous (IV) vancomycin (serum trough 15-20 μg/mL) in 38-79% of cases. Airway blood flow is diminished compared to alveoli and we hypothesized that vancomycin concentrations achieved in airway secretions are suboptimal and nonbactericidal. Targeted therapy by inhalation may overcome this deficit.

METHODS

Airway pharmacokinetics of optimized IV and inhaled vancomycin in infected clinically stable prolonged mechanically ventilated patients were measured. First, IV vancomycin was given until optimized concentrations were achieved (15-20 μg/mL), and, at the same time point, sputum vancomycin concentrations were measured. Then, sputum concentrations were re-assessed after 4 treatments of inhaled vancomycin (120 mg/2 mL) via a previously characterized nebulizing system that deposited 18 ± 2 mg in the lungs. Vancomycin post-distribution phase serum peak and trough concentrations were also obtained. Serum albumin was measured to assess binding to vancomycin.

RESULTS

Mean serum trough concentration was 18.4 ± 6.5 μg/mL. Sputum concentrations were affected by serum albumin. Only patients with severe hypoalbuminaemia had penetration of drug leading to therapeutic (15.7-17 μg/mL) sputum concentrations. Following inhaled vancomycin, sputum concentrations increased significantly to 199 ± 37.0 μg/mL (P = .002) exceeding minimum inhibitory concentration by 2 orders of magnitude.

CONCLUSION

Despite optimized serum concentrations, patients with albumin near normal had suboptimal concentrations of vancomycin in their sputum. Inhaled therapy may be clinically important for successful treatment of ventilator-associated methicillin-resistant Staphylococcus aureus infection. Further studies of inhaled therapy are needed to define their role as adjunctive therapy in ventilator-associated pneumonia and as single therapy in tracheobronchitis.

Population pharmacokinetics and dosing simulations of meropenem in septic critically ill patients with complicated intra-abdominal infection or pneumonia

OBJECTIVES

Meropenem pharmacokinetics (PK) may be altered in septic critically ill patients with complicated intra-abdominal infections (cIAI) and pneumonia. We aimed to evaluate the covariates affecting meropenem PK and the performance of different dosing regimens to optimize the PK/pharmacodynamic target.

METHODS

Population PK analysis was performed using non-linear mixed-effects modeling. The final model was validated and used to simulate meropenem exposure to assess the probability of attaining the 100 %ƒT>MIC target.

RESULTS

Forty-six and 14 patients were respectively enrolled for PK analysis and external validation. A one-compartment linear model adequately described the data of 226 concentrations. The typical clearance (CL) and volume of distribution (Vd) were 9.69 L/h and 27.4 L, respectively. Septic shock from cIAI (cIASS) and actual body weight were significant covariates for meropenem Vd in addition to the influential covariates of creatinine clearance (CLCR-CG) and augmented renal clearance for CL. External validation showed the robustness and accuracy of this model. Simulation results proposed continuous infusion (CI) dosing regimens of meropenem against pathogens with MICs ≥ 2 mg/L in patients with cIASS and CLCR-CG ≥ 60 mL/min.

CONCLUSIONS

For the patients with cIASS and CLCR-CG ≥ 60 mL/min, CI meropenem is proposed for treatment of less sensitive pathogens with MICs ≥ 2 mg/L.

Clinical outcomes in ventilator-associated pneumonia patients with and without chronic obstructive pulmonary disease

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is the third leading cause of death worldwide. Critically ill patients with COPD exacerbations may require invasive mechanical ventilation (IMV). Ventilator-associated pneumonia (VAP) commonly occurs in the intensive care unit (ICU) and is usually associated with high mortality. Current studies on the association between COPD and VAP are limited. This work compared the causes and clinical outcomes of VAP in patients with and without COPD in Taiwan.

METHODS

This retrospective observational study was conducted at the Chiayi Chang Gung Memorial Hospital. Patients diagnosed with VAP were enrolled between January 2015 and December 2019. The COPD diagnosis was based on postbronchodilator pulmonary function tests. We compared the bacterial cause, ICU and hospital stay length, IMV duration and mortality rates in patients with and without COPD.

RESULTS

A total of 175 patients with VAP were enrolled, 44% of whom presented had preexisting COPD. The disease severity on the day of admission was similar in both groups. Microorganisms were identified in 83 (47%) patients, with Pseudomonas aeruginosa , Acinetobacter spp., and Klebsiella pneumoniae being the most common pathogens. The proportion of multidrug resistant isolates showed no significant differences between groups. Most patients underwent antibiotic treatment before VAP onset. The length of ICU and hospital stays and IMV duration after VAP onset were similar between the two groups, as well as ICU mortality, in-hospital mortality, and 14-day mortality.

CONCLUSION

Our study revealed that COPD was not associated with worse clinical outcomes in patients with VAP. No significant differences in bacterial cause were observed between the two groups.

Oral hygiene in critically ill patients at a tertiary hospital in São Paulo, Brazil: a best practice implementation project

OBJECTIVES

This project aimed to promote evidence-based practices relat. ed to the oral health of critically ill patients in an intensive care unit in Brazil.

INTRODUCTION

The oral hygiene of patients on mechanical ventilation is an essential component of nursing care quality, and well-defined guidelines ensure appropriate care. Mechanical ventilation is associated with the risk of ventilator-associated pneumonia, which can increase mortality, length of stay, time on mechanical ventilation, and hospital costs.

METHODS

This project was guided by the JBI Evidence Implementation Framework, which consists of seven stages: (1) identification of the area of practice to be changed, (2) involvement of change agents, (3) context assessment and readiness for change, (4) review of practices against evidence-based audit criteria, (5) implementation of practice changes, (6) reassessment of practices using a follow-up audit, and (7) consideration of the sustainability of changes in practice.

RESULTS

Four audit criteria were developed to evaluate compliance with best practices. In the follow-up audit, Criteria 1, 2, and 3 obtained compliance of ≥ 80%. Thus, for Criterion 1, all the patients on mechanical ventilation for more than 24 hours were evaluated by the oral medicine team, resulting in 100% compliance. For Criterion 2 on appropriate oral hygiene measures, a compliance rate of 80% was achieved. For Criterion 3, 39 professionals (90.7%) participated in educational activities related to the oral health protocol for critically ill patients, obtaining 90.7% compliance. For Criterion 4 regarding patients being evaluated before receiving any oral health care, improvement was low (only 50%), revealing the need for further improvement.

CONCLUSION

This best practice project improved the professional practice of nursing staff and increased compliance with best practices for the oral health of critically ill patients.

SPANISH ABSTRACT

http://links.lww.com/IJEBH/A175.

Impact of the microscopic quality of endotracheal aspirates on the performance of the Filmarray® pneumonia plus panel in intensive care unit patients with suspected lower respiratory tract infection

PURPOSE

We investigated how the microscopic quality of endotracheal aspirates (ETA) impacts the performance of the Filmarray® pneumonia plus panel (FA-PP) in patients undergoing mechanical ventilation (IMV) with suspicion of lower respiratory tract bacterial infection (LRTBI).

METHODS

The quality of ETA was categorized according to the number of leukocytes and buccal squamous epithelial (BSE)/field (100x magnification). G5 (< 10 BSE cells and > 25 leukocytes/field) and G4 (10-25 BSE cells and > 25 leukocytes/field) ETA were tested in parallel by the FA-PP and conventional semiquantitative culture.

RESULTS

In total, 153 ETA were graded as G5 (from 115 patients) and 56 as G4 (from 48 patients). Focusing on "conventional" bacterial species, a trend towards more positive results (P = 0.16), and co-detections (P = 0.18) was returned by G5 ETA. Although more targets were detected on G5 ETA (P = 0.005), the spectra of bacteria detected was comparable across G5 and G4 specimens. A trend towards higher bacterial burdens as quantitated by the FA-PP, and irrespective of the target, was observed in G5 (median, 106 genome copies/ml) vs. G4 ETA (median, 105 genome copies/ml). The degree of full agreement between FA-PP and culture was higher for G5 ETA (Kappa value, 0.54; 95% CI, 0.43-0.66) than for G4 ETA (Kappa value, 0.31; 95% CI, 0.11-0.49). For all bacterial targets detected, genome copy/ml numbers exceeded colony forming units (CFU)/ml counts in 1-2 log10, irrespective of ETA grading. The degree of correlation between genome copies/ml and CFU/ml was slightly better for G5 ETA (Rho = 0.65; P = 0.001) than for G4 ETA (Rho = 0.54; P = 0.11).

CONCLUSION

FA-PP testing of G5 ETA may provide more comprehensive and clinically useful information compared with G4 specimens in patients undergoing IMV with suspected LRTBI and receiving antimicrobial therapy. Yet G4 ETA may still provide useful microbiological information.

Clinical Differences Between Survivors and Non-Survivors of Ventilator-Associated Pneumonia: The Roles of Sulbactam/Ampicillin and Methicillin-Resistant Staphylococcus aureus

Background

Ventilator-associated pneumonia (VAP) is one of the most lethal complications in intensive care unit (ICU) patients. However, critical issues of non-survivors vary and are still unclear in VAP patients.

Methods

The clinical differences between survivors and non-survivors of VAP were retrospectively analyzed in patients hospitalized from April 2023 to March 2024.

Results

Of a total of 42 VAP patients, 22 (52.4%) survived, and 20 died. Survivors were significantly younger (69.1 vs 71.7 years, p < 0.01) and received sulbactam/ampicillin (SAM) as the initial antibiotics, significantly more (45.5% vs 10%, p = 0.006) than non-survivors. The male/female ratio and wards where they were managed were similar in both groups, but methicillin-resistant Staphylococcus aureus (MRSA) was detected significantly more frequently in non-survivors (4/4 = 100%).

Conclusion

These data suggest that VAP patients who survived were younger and received treatment with narrow-spectrum antibiotics, such as SAM. Isolation of MRSA might be critical. These findings could influence antibiotic protocols and ICU management strategies to prevent infection with resistant bacteria to improve the prognosis of patients with VAP.

Association between serum endocan levels and organ failure in hospitalized patients with cirrhosis

BACKGROUND & AIMS

Acute-on-chronic liver failure is a syndrome characterized by organ failure and high short-term mortality. The lack of reliable biomarkers for the early detection of acute-on-chronic liver failure is a significant challenge. Endothelial dysfunction plays a key role in the development of organ failure. Serum endocan is a potential new biomarker for endothelial dysfunction. Therefore, this study aimed to assess the association between endocan and organ failure and 28-day mortality in patients with cirrhosis.

METHODS

Hospitalized patients with cirrhosis with and without organ failure were prospectively enrolled according to the criteria of the European Association for the Study of Liver-Chronic Liver Failure consortium. The comparative performances of serum endocan, procalcitonin, and interleukin-6 for diagnosing organ failure and predicting mortality were studied.

RESULTS

The study included 116 hospitalized patients with cirrhosis, 55 of whom had organ failure on admission. Patients with organ failure had significantly higher endocan, procalcitonin, and interleukin-6 levels than those without it. At a cut-off value of 15.8 ng/mL, endocan showed a sensitivity of 63.6% and specificity of 67.2% for the diagnosis of organ failure, with an area under the receiver operating characteristic curve of 0.65, which is comparable to procalcitonin and interleukin-6. Multivariate analysis identified serum endocan, creatinine, and total bilirubin as independent factors for organ failure in hospitalized patients with cirrhosis. Patients who died within 28 days had significantly higher baseline biomarker levels than those who survived. Liver failure, hospital-acquired infection, mechanical ventilator use, and interleukin-6 ≥37 pg/mL were independent predictors of 28-day mortality.

CONCLUSION

Serum endocan is associated with organ failure and is an independent risk factor of organ failure in hospitalized patients with cirrhosis.

Management of Ventilator-Associated Pneumonia Caused by Pseudomonas and Acinetobacter Organisms in a Pediatric Center: A Randomized Controlled Study

A dangerous infection contracted in hospitals, ventilator-associated pneumonia is frequently caused by bacteria that are resistant to several drugs. It is one of the main reasons why patients in intensive care units become ill or die. This research aimed to determine the most effective empirical therapy of antibiotics for better ventilator-associated pneumonia control and to improve patient outcomes by using the minimal inhibitory concentration method and the Ameri-Ziaei double antibiotic synergism test and by observing the clinical responses to both single and combination therapies. Patients between the ages of one month and twelve who had been diagnosed with ventilator-associated pneumonia and had been on mechanical ventilation for more than 48 h were included in the study, which was carried out in the Pediatric Intensive Care Unit at Cairo University's Hospital. When ventilator-associated pneumonia is suspected, it is critical to start appropriate antibiotic therapy as soon as possible. This is especially important in cases where multidrug-resistant Gram-negative infections may develop. Although using Polymyxins alone or in combination is effective, it is important to closely monitor their administration to prevent resistance from increasing. The combination therapy that showed the greatest improvement was a mix of aminoglycosides, quinolones, and β-lactams. A combination of aminoglycosides and dual β-lactams came next. Although the optimal duration of antibiotic treatment for ventilator-associated pneumonia is still unknown, treatments longer than seven days are usually required to eradicate MDR P. aeruginosa or A. baumannii completely.

Piperacillin/Tazobactam Susceptibility Test Interpretive Criteria for Enterobacterales: Recommendations From the United States Committee on Antimicrobial Susceptibility Testing

The in vitro susceptibility testing interpretive criteria (STIC) for piperacillin/tazobactam (TZP) against Enterobacterales were recently updated by the US Food and Drug Administration, Clinical and Laboratory Standards Institute, and European Committee on Antimicrobial Susceptibility Testing. The United States Committee on Antimicrobial Susceptibility Testing (USCAST) also recently reviewed TZP STIC for Enterobacterales and arrived at different STIC for Enterobacterales. Here, we explain our recommendations and rationale behind them. Based on our review of the available data, USCAST does not recommend TZP STIC for certain Enterobacterales species that have a moderate to high likelihood of clinically significant AmpC production (Enterobacter cloacae, Citrobacter freundii, and Klebsiella aerogenes only) or for third-generation cephalosporin-nonsusceptible Enterobacterales. USCAST recommends a TZP susceptibility breakpoint of ≤ 16/4 mg/L for third-generation cephalosporin-susceptible Enterobacterales and only endorses the use of extended infusion TZP regimens for patients with infections due to these pathogens.

Use of fluoroquinolones and risk of rhegmatogenous retinal detachment: a retrospective cohort study using two nationwide representative claims databases

Background

Although biological plausibility suggests that fluoroquinolones could lead to rhegmatogenous retinal detachment (RRD) through collagen degradation, real-world evidence on their relative risk of RRD is inconsistent, with limited information on absolute risk estimates.

Objective

The study aimed to estimate the RRD risk associated with fluoroquinolones versus other antibiotics with similar indications (i.e., comparison antibiotics).

Methods

We conducted a retrospective cohort study analyzing claims data from adult patients who initiated fluoroquinolones or amoxicillin/clavulanate or ampicillin/sulbactam or extended-spectrum cephalosporins using the Taiwan National Health Insurance Research Database (2009-2018) and the United States IBM MarketScan Database (2011-2020). Patients were followed for up to 90 days after cohort entry. For each country's data, after 1:1 propensity score (PS) matching, we used Cox regression models to estimate RRD risks, presented with hazard ratios (HR) with 95% confidence interval (95% CI). We used random-effects meta-analyses to derive pooled HRs across both counties.

Results

Of 24,172,032 eligible patients comprising 7,944,620 insured Taiwanese (mean age [SD], 46 [18] years; 45% male) and 16,227,412 United States commercially insured individuals (mean age [SD], 47 [16] years; 40% male), 10,137,468 patients initiated fluoroquinolones, 10,203,794 initiated amoxicillin/clavulanate or ampicillin/sulbactam, and 3,830,770 initiated extended-spectrum cephalosporins. After PS matching, similar RRD incidence rates were observed between fluoroquinolones and amoxicillin/clavulanate or ampicillin/sulbactam users (0.33 [95% CI, 0.19-0.56] versus 0.35 [95% CI, 0.26-0.46] per 1,000 person-years), yielding an HR of 0.97 (95% CI, 0.76-1.23). The RRD incidence rates were also similar comparing fluoroquinolones to extended-spectrum cephalosporins (0.36 [95% CI, 0.22-0.57] versus 0.34 [95% CI, 0.22-0.50] per 1,000 person-years; HR, 1.08 [95% CI, 0.92-1.27]). The comparative safety profiles remained consistent by country, various patient characteristic (e.g., diabetes or ophthalmic conditions), type of fluoroquinolones, follow-up duration, or treatment setting.

Conclusion

This large-scale study, leveraging real-world data from Taiwan and the United States, showed a low and comparable RRD risk among adults who initiated fluoroquinolones or other antibiotics with similar indications. This suggests that the RRD risk should not deter the use of fluoroquinolone when clinically indicated.

Predictive validity of interleukin 6 (IL-6) for the mortality in critically ill COVID-19 patients with the B.1.617.2 (Delta) variant in Vietnam: a single-centre, cross-sectional study

OBJECTIVES

To investigate the serum IL-6 levels and their rate of change in predicting the mortality of critically ill patients with COVID-19 in Vietnam.

DESIGN

A single-centre, cross-sectional study.

SETTING

An Intensive Care Centre for the Treatment of Critically Ill Patients with COVID-19 in Ho Chi Minh City, Vietnam.

PARTICIPANTS

We included patients aged 18 years or older who were critically ill with COVID-19 and presented to the study centre from 30 July 2021 to 15 October 2021. We excluded patients who did not have serum IL-6 measurements between admission and the end of the first day.

PRIMARY OUTCOME MEASURES

The primary outcome was hospital all-cause mortality.

RESULTS

Of 90 patients, 41.1% were men, the median age was 60.5 years (Q1-Q3: 52.0-71.0), and 76.7% of patients died in the hospital. Elevated IL-6 levels were observed on admission (41.79 pg/mL; Q1-Q3: 20.68-106.27) and on the third day after admission (72.00 pg/mL; Q1-Q3: 26.98-186.50), along with a significant rate of change in IL-6 during that period (839.5%; SD: 2753.2). While admission IL-6 level (areas under the receiver operator characteristic curve (AUROC): 0.610 (95% CI: 0.459 to 0.761); cut-off value ≥15.8 pg/mL) and rate of change in IL-6 on the third day of admission (AUROC: 0.586 (95% CI: 0.420 to 0.751); cut-off value ≥-58.7%) demonstrated poor discriminatory ability in predicting hospital mortality, the third day IL-6 rate of change from admission ≥-58.7% (adjusted OR: 12.812; 95% CI: 2.104 to 78.005) emerged as an independent predictor of hospital mortality.

CONCLUSIONS

This study focused on a highly selected cohort of critically ill COVID-19 patients with a high IL-6 level and mortality rate. Despite the poor discriminatory value of admission IL-6 levels, the rate of change in IL-6 proved valuable in predicting mortality. To identify critically ill COVID-19 patients with the highest risk for mortality, monitoring the serial serum IL-6 measurements and observing the rate of change in serum IL-6 levels over time are needed.

Evaluation of a Pharmacist-Led Methicillin-Resistant Staphylococcus aureus Nasal PCR Testing Protocol

Background/Objectives: Methicillin-resistant Staphylococcus aureus (MRSA) can cause cases of community-acquired pneumonia, hospital-acquired pneumonia, and ventilator-associated pneumonia, and nasal colonization with this pathogen increases the risk of infection. Due to its high negative predictive value, multiple studies support using the MRSA nasal polymerase chain reaction (PCR) test to discontinue antimicrobials that target MRSA in the setting of a negative test result. The purpose of this project was to assess the utility of a protocol to allow pharmacists the ability to order MRSA nasal PCR screenings in hospitalized patients with pneumonia. Results: The pre-protocol group included a random sample of 100 patients, and the post-protocol group included 625 patients. Vancomycin DOTs when pharmacists ordered PCRs were significantly lower compared to the pre-protocol group (p < 0.5; 95% CI, 0.46-2.24). The average length of stay and readmission rates at 30 days were significantly lower in the post-protocol group compared to the pre-protocol group (p < 0.05 and p = 0.02, respectively), but there was no significant difference in mortality (p = 0.33). Methods: A protocol was implemented at our institution that allowed pharmacists to order an MRSA nasal PCR test in patients with pneumonia. This retrospective chart review compared a cohort of patients who received vancomycin from before implementation of the protocol to patients who received vancomycin after the protocol's implementation. The primary endpoint was vancomycin days of therapy (DOTs) between the pre-protocol group and the post-protocol group. Other endpoints assessed included the length of hospitalization, readmission rates, and mortality. Conclusions: Pharmacists ordering MRSA nasal PCR tests significantly reduced vancomycin DOTs, average length of stay, and 30-day readmission rates, contributing to positive outcomes in patients with pneumonia.

Potential Synergy of Fluoxetine and Antibacterial Agents Against Skin and Soft Tissue Pathogens and Drug-Resistant Organisms

Background/Objectives: The feasibility of repurposing selective serotonin reuptake inhibitors as adjunctive antibacterial agents is an area of current investigation. We sought to evaluate if fluoxetine will achieve synergistic killing with relevant antibacterial drugs against skin and soft tissue pathogens and multidrug-resistant pathogens. Methods: The MIC of fluoxetine was determined using broth microdilution for a diverse isolate collection of 21 organisms. Checkerboard experiments were then conducted using fluoxetine and clinically relevant antibacterial drugs. If fluoxetine and an anti-infective agent achieved synergy denoted by a fractional inhibitory concentration index ≤ 0.5, then the combination was further evaluated in 24 h time-killing experiments. Synergy in time-killing experiments was defined as a ≥2 log10 CFU/mL reduction in fluoxetine combined with an antibacterial agent at any point in the experiment in comparison to whichever agent in the combination resulted in the lowest bacterial counts individually. Results: The fluoxetine MICs ranged from 64 to 128 mcg/mL for Gram-positive isolates and 8-512 mcg/mL for Gram-negative organisms. Against Gram-positive isolates, vancomycin, linezolid, clindamycin, and gentamicin failed to achieve synergy in checkerboard experiments. Levofloxacin and fluoxetine were the only combination that demonstrated synergy against a Gram-positive pathogen in both checkerboard and time-killing experiments (1/6 isolates, 16.7%). Against Gram-negative organisms, the most promising combination was fluoxetine and polymyxin B, which achieved synergistic killing in both checkerboard experiments and time-killing experiments in 12/15 isolates (80%). In comparison, fosfomycin and meropenem achieved synergy in both experiments against 6/15 (40%) and 3/15 (20%) Gram-negative isolates, respectively. Conclusions: The combination of fluoxetine and polymyxin B may be a potential strategy for combatting difficult-to-treat Gram-negative pathogens.

Knowledge, attitudes and practices on prevention and control of high-consequence infectious diseases and critical care among intensive care personnel in Rwanda: a cross-sectional survey

Introduction

Intensive care personnel in countries prone to outbreaks of high-consequence infectious diseases (HCIDs), such as Ebola virus disease, stand at the forefront of caring for affected patients. This study describes the knowledge, attitudes and practices (KAP) of intensive care personnel in Rwanda on the management and infection prevention and control (IPC) of HCIDs.

Methods

A cross-sectional survey was carried out among staff working in the 4 operational intensive care units in September 2022. The self-administered questionnaire collected information on participants' background and their KAP on critical care (CC), HCIDs and IPC.

Results

Of the 107 participants, 67 (62.6%) had less than 4 years' work experience in CC. 41 (38.3%) of them had attended trainings on IPC since 2020. In univariate analyses, a higher knowledge score was associated with being a physician, years of working in CC and differed by hospital. A large proportion perceived their knowledge on CC as good or very good (58.0%) and their everyday risk of acquiring an infection as at least high (48.6%). Overall, 72.9% reported compliance with hand hygiene measures. However, around a quarter of participants reported rarely or never avoiding recapping of needles or never or rarely taking additional precautions during aerosol-generating procedures.

Conclusions

Staff had a moderate knowledge base and might benefit from continuous learning on CC and HCIDs. The perception of high risk of infection at work stands in contrast with lack of compliance with basic IPC practices which should be reinforced to avoid preventable and potentially fatal infections.

Predictive values of methicillin-resistant Staphylococcus aureus nasal swabs for pneumonia in burn ICU patients

INTRODUCTION/OBJECTIVE

This retrospective cohort study aimed to determine the sensitivity, specificity, and positive (PPV) and negative predictive values (NPV) of MRSA nasal swabs for pneumonia in burn-injured intensive care unit (ICU) patients.

METHODS

Patients 18 years or older admitted to the Burn ICU at a tertiary medical center from 2016 to 2021 were included if they had any burns, a pneumonia ICD-10 code, an MRSA nasal swab obtained during admission, and any respiratory cultures associated with at least five consecutive days of antibiotics.

RESULTS

There were 267 occurrences of pneumonia across 136 patients. MRSA nasal swabs had an overall sensitivity of 39 %, specificity of 98.7 %, PPV of 84.2 %, and NPV of 89.9 %. MRSA nasal swabs obtained less than seven days from antibiotic initiation had a specificity of 98.6 % and NPV of 98.6 %; meanwhile, swabs obtained at least seven days from antibiotic initiation had a specificity of 98.7 % and NPV of 86.4 %.

CONCLUSIONS

The high specificity and NPV indicate that negative MRSA nasal swabs obtained less than seven days from antibiotic initiation may be used to de-escalate anti-MRSA antibiotics in clinically stable burn-injured patients with suspicion of pneumonia. The decrease in NPV suggests that it may be beneficial to obtain a repeat swab periodically.

Prediction models for the risk of ventilator-associated pneumonia in patients on mechanical ventilation: A systematic review and meta-analysis

BACKGROUND

Identifying patients at risk of ventilator-associated pneumonia through prediction models can facilitate medical decision-making. Our objective was to evaluate the current models for ventilator-associated pneumonia in patients with mechanical ventilation.

METHODS

Nine databases systematically retrieved from establishment to March 6, 2024. Two independent reviewers performed study selection, data extraction, and quality assessment, respectively. The Prediction Model Risk of Bias Assessment Tool was used to evaluate the risk of model bias and applicability. Stata 17.0 was used to conduct a meta-analysis of discrimination of model validation.

RESULTS

The total of 34 studies were included, with reported 52 prediction models. The most frequent predictors in the models were mechanical ventilation duration, length of intensive care unit stay, and age. Each study was essentially considered having a high risk of bias. A meta-analysis of 17 studies containing 33 models with validation was performed with a pooled area under the receiver-operating curve of 0.80 (95% confidence interval: 0.78-0.83).

CONCLUSIONS

Despite the relatively excellent performance of the models, there is a high risk of bias of the model development process. Enhancing the methodological quality, especially the external validation, practical application, and optimization of the models need urgent attention.

Therapy of Aspiration: Out-of-Hospital and In-Hospital-Acquired

Therapeutic considerations for aspiration pneumonia prioritize the risk of multidrug-resistant organisms. This involves integrating microbiological insights with each patient's unique risk profile, including the location at the time of aspiration, and whether it occurred in or out of the hospital. Our understanding of the microbiology of aspiration pneumonia has also evolved, leading to a reassessment of anaerobic bacteria as the primary pathogens. Emerging research shows a predominance of aerobic pathogens, in both community and hospital-acquired cases. This shift challenges the routine use of broad-spectrum antibiotics targeting anaerobes, which can contribute to antibiotic resistance and complications such as Clostridium difficile infections-concerns that are especially relevant given the growing issue of antimicrobial resistance. Adopting a comprehensive, patient-specific approach that incorporates these insights can optimize antibiotic selection, improve treatment outcomes, and reduce the risk of resistance and adverse effects.

Key summary of German national guideline for adult patients with nosocomial pneumonia- Update 2024 Funding number at the Federal Joint Committee (G-BA): 01VSF22007

PURPOSE

This executive summary of a German national guideline aims to provide the most relevant evidence-based recommendations on the diagnosis and treatment of nosocomial pneumonia.

METHODS

The guideline made use of a systematic assessment and decision process using evidence to decision framework (GRADE). Recommendations were consented by an interdisciplinary panel. Evidence analysis and interpretation was supported by the German innovation fund providing extensive literature searches and (meta-) analyses by an independent methodologist. For this executive summary, selected key recommendations are presented including the quality of evidence and rationale for the level of recommendation.

RESULTS

The original guideline contains 26 recommendations for the diagnosis and treatment of adults with nosocomial pneumonia, thirteen of which are based on systematic review and/or meta-analysis, while the other 13 represent consensus expert opinion. For this key summary, we present 11 most relevant for everyday clinical practice key recommendations with evidence overview and rationale, of which two are expert consensus and 9 evidence-based (4 strong, 5 weak and 2 open recommendations). For the management of nosocomial pneumonia patients should be divided in those with and without risk factors for multidrug-resistant pathogens and/or Pseudomonas aeruginosa. Bacterial multiplex-polymerase chain reaction (PCR) should not be used routinely. Bronchoscopic diagnosis is not considered superior to´non-bronchoscopic sampling in terms of main outcomes. Only patients with septic shock and the presence of an additional risk factor for multidrug-resistant pathogens (MDRP) should receive empiric combination therapy. In clinically stabilized patients, antibiotic therapy should be de-escalated and focused. In critically ill patients, prolonged application of suitable beta-lactam antibiotics should be preferred. Therapy duration is suggested for 7-8 days. Procalcitonin (PCT) based algorithm might be used to shorten the duration of antibiotic treatment. Patients on the intensive care unit (ICU) are at risk for invasive pulmonary aspergillosis (IPA). Diagnostics for Aspergillus should be performed with an antigen test from bronchial lavage fluid.

CONCLUSION

The current guideline focuses on German epidemiology and standards of care. It should be a guide for the current treatment and management of nosocomial pneumonia in Germany.

Longitudinal two-year comparative genomic analysis of respiratory Staphylococcus aureus isolates from intensive care unit mechanically ventilated patients

BACKGROUND

Ventilator-associated pneumonia (VAP) is the main healthcare-associated infection in intensive care units with Staphylococcus aureus as the first pathogen in early VAP.

AIM

To compare, using whole-genome sequencing (WGS), consecutive S. aureus isolates from lower respiratory samples of mechanically ventilated patients for identification of potential cross-transmissions; and to determine a potential link between S. aureus WGS data and patients with S. aureus early VAP.

METHODS

All mechanically ventilated patients with a documentation of respiratory S. aureus isolates were included over a two-year period. WGS allowed typing, comparative genomic and phylogenic analyses, as well as analyses of antibiotic resistance genes and virulence genes. Virulence genes were compared between patients who developed respiratory infectious event and those who did not.

FINDINGS

A total of 172 S. aureus isolates from 167 patients were sequenced. WGS revealed that the S. aureus population was polyclonal with only two potential healthcare cross-transmissions, each involving two isolates (2.3%). A very low resistance rate was observed with a strong genotypic/phenotypic association, and with a virulence profile highly dependent on the sequence type. No significant correlation was observed between VAP and virulence profile.

CONCLUSION

This study on consecutive respiratory S. aureus isolates of mechanically ventilated patients revealed a very low level of cross-transmission. No association was observed between S. aureus WGS data and VAP occurrence.

Nosocomial Pneumonia in Georgia: A Study of Extended Spectrum Beta-Lactamase (ESBL)-Producing Versus Non-extended ESBL Gram-Negative Bacterial Profiles

BACKGROUND

Nosocomial pneumonia is a significant healthcare challenge, particularly in the face of rising antimicrobial resistance among Gram-negative bacteria. The production of extended spectrum beta-lactamase (ESBL) exacerbates treatment complexities.

AIM

This study investigates the prevalence and resistance patterns of ESBL-producing and non-ESBL Gram-negative bacteria in nosocomial pneumonia cases in Georgian hospitals to inform antibiotic stewardship and treatment strategies. To our knowledge, this is the first study of its kind conducted in Georgia, offering critical insights into bacterial resistance in this region.

METHODS

This prospective observational study analyzed a total of 357 pulmonary samples from patients diagnosed with nosocomial pneumonia in Georgian hospitals between December 2022 and February 2024. Gram-negative bacterial identification and ESBL determination were performed using the combination disk method, adhering to European Committee on Antimicrobial Susceptibility Testing (EUCAST) standards. The analyses were conducted at TEST-IMP Laboratory and the Richard Lugar Center for Public Health Research to investigate the prevalence and resistance patterns of ESBL-producing versus non-ESBL Gram-negative bacteria.

RESULTS

Among the 256 Gram-negative isolates, 201 (78.5%) were ESBL producers. Pseudomonas aeruginosa (63.7%), Acinetobacter baumannii (18.4%), and Klebsiella pneumoniae (17.9%) were the most prevalent. Non-ESBL producers accounted for 21.5% but exhibited notable beta-lactamase activity. The remaining 101 samples were evaluated as an additional analysis, revealing the distribution of Gram-positive bacteria and fungi as outlined in the results. However, the primary emphasis of this study remains on the resistance patterns and prevalence of Gram-negative pathogens.

CONCLUSIONS

The study highlights a concerning prevalence of ESBL-producing bacteria in nosocomial pneumonia cases, emphasizing the urgent need for improved antibiotic stewardship and infection control practices in Georgian hospitals. Non-ESBL producers displayed susceptibility to advanced antibiotics, presenting potential therapeutic opportunities, though vigilance is required to prevent further resistance development.

PaCO2 Association with Outcomes of Patients with Traumatic Brain Injury at High Altitude: A Prospective Single-Center Cohort Study

BACKGROUND

Partial pressure of carbon dioxide (PaCO2) is generally known to influence outcome in patients with traumatic brain injury (TBI) at normal altitudes. Less is known about specific relationships of PaCO2 levels and clinical outcomes at high altitudes.

METHODS

This is a prospective single-center cohort of consecutive patients with TBI admitted to a trauma center located at 2600 m above sea level. An unfavorable outcome was defined as a Glasgow Outcome Scale-Extended (GOSE) score < 4 at the 6-month follow-up.

RESULTS

We had a total of 81 patients with complete data, 80% (65/81) were men, and the median (interquartile range) age was 36 (25-50) years. Median Glasgow Coma Scale (GCS) score on admission was 9 (6-14); 49% (40/81) of patients had severe TBI (GCS 3-8), 32% (26/81) had moderate TBI (GCS 12-9), and 18% (15/81) had mild TBI (GCS 13-15). The median (interquartile range) Abbreviated Injury Score of the head (AISh) was 3 (2-4). The frequency of an unfavorable outcome (GOSE < 4) was 30% (25/81), the median GOSE was 4 (2-5), and the median 6-month mortality rate was 24% (20/81). Comparison between patients with favorable and unfavorable outcomes revealed that those with unfavorable outcome were older, (median age 49 [30-72] vs. 29 [22-41] years, P < 0.01), had lower admission GCS scores (6 [4-8] vs. 13 [8-15], P < 0.01), had higher AISh scores (4 [4-4] vs. 3 [2-4], P < 0.01), had higher Acute Physiology and Chronic Health disease Classification System II scores (17 [15-23] vs. 10 [6-14], P < 0.01), had higher Charlson scores (0 [0-2] vs. 0 [0-0], P < 0.01), and had higher PaCO2 levels (mean 35 ± 8 vs. 32 ± 6 mm Hg, P < 0.01). In a multivariate analysis, age (odds ratio [OR] 1.14, 95% confidence interval [CI] 1.1-1.30, P < 0.01), AISh (OR 4.7, 95% CI 1.55-21.0, P < 0.05), and PaCO2 levels (OR 1.23, 95% CI 1.10-1.53, P < 0.05) were significantly associated with the unfavorable outcomes. When applying the same analysis to the subgroup on mechanical ventilation, AISh (OR 5.4, 95% CI 1.61-28.5, P = 0.017) and PaCO2 levels (OR 1.36, 95% CI 1.13-1.78, P = 0.015) remained significantly associated with the unfavorable outcome.

CONCLUSIONS

Higher PaCO2 levels are associated with an unfavorable outcome in ventilated patients with TBI. These results underscore the importance of PaCO2 levels in patients with TBI and whether it should be adjusted for populations living at higher altitudes.

Prevalence and molecular characterization of carbapenem-resistant Enterobacterales in patients from a public referral hospital in a non-metropolitan region of Brazil during and post the SARS-CoV-2 pandemic

Antimicrobial resistance (AMR) poses a global threat, with carbapenem-resistant Enterobacterales (CRE) representing a significant concern due to limited therapeutic options. This study investigated the prevalence of carbapenemase genes in CRE strains isolated from tracheal aspirates of patients at a Brazilian university hospital between January 2020 and August 2023. Bacterial identification was conducted using MALDI-TOF, while carbapenemase genes were detected by qPCR. Demographic and clinical data were collected, and univariate analysis was performed using the chi-square test (p < 0.05). Variables with p ≤ 0.10 were further investigated using the chi-square test for linear trend, along with stratified analysis. Out of 1,133 samples, 111 (9.79%) showed CRE growth, with 46 isolates included in the final sample, predominantly comprising Klebsiella pneumoniae (65.21%) and Serratia marcescens (19.57%). The blaKPC gene was prevalent (78.26%), while blaNDM was detected in 21.74% of cases. The identified population was predominantly male (67.39%), elderly (69.57%), white (56.52%), unmarried (63.04%), and had a low level of education (56.52%). Most patients (69.57%) were in the intensive care unit and remained hospitalized for more than 30 days (76.08%). There was a significant inverse trend between Klebsiella pneumoniae and age (p = 0.045), as well as a direct linear trend between blaNDM and the annual increase in COVID-19 cases in Brazil (p = 0.050). A high probability of finding non-Klebsiella pneumoniae bacteria was observed in patients with prolonged hospital stays, independent of COVID-19 (p = 0.006) and the type of resistance genes (p = 0.020). The persistent prevalence of CRE, especially with blaKPC, underscores the urgency of effective control measures.

Improving pharmacokinetic/pharmacodynamic outcomes of antimicrobial therapy for pneumonia in the ICU

INTRODUCTION

Pneumonia remains a significant global health challenge due to its high prevalence and mortality rate, and challenging treatment. This review explores the best strategies to optimize the antibiotic therapy for pneumonia in critically ill patients, focusing on pharmacokinetics, pharmacodynamics, and therapeutic data.

AREAS COVERED

A review of scientific publications on severe pneumonia highlights the challenges of optimizing antibiotic use to improve lung diffusion, bacterial killing, and achieving PK/PD targets, emphasizing the need to understand microbiological epidemiology and MIC breakpoints. Key strategies like nebulization, therapeutic drug monitoring, and emerging technologies such as ELF TDM and nanomaterial-based drug delivery systems are essential for optimizing PK/PD outcomes and addressing antimicrobial resistance.

EXPERT OPINION

Improving our understanding of pulmonary pharmacokinetics and optimizing their tissue diffusion are instrumental for achieving precision antibiotic therapy for severe pneumonia. By addressing current limitations and embracing interdisciplinary collaboration, we can pave the way for more efficient personalized approaches in infectious disease management.

Intravenous combined with aerosolised polymyxins vs intravenous polymyxins monotherapy for ventilator-associated pneumonia: A systematic review and meta-analysis

Polymyxins were applied via different administration routes to treat ventilator-associated pneumonia (VAP) caused by carbapenem-resistant Gram-negative bacteria (CR-GNB). The potential benefits of aerosolised polymyxins as adjunctive treatment for patients are contradictory. This review assessed the safety and efficacy of intravenous (IV) combined with aerosolised polymyxins vs IV polymyxins monotherapy in patients with VAP caused by CR-GNB. Two reviewers independently evaluated and extracted data from PubMed, Embase, Cochrane library and Web of Science. The primary outcome was all-cause mortality and secondary outcomes included clinical cure rate, clinical improvement rate, microbiological eradication rate and nephrotoxicity. Differences for dichotomous outcomes were expressed as odds ratios (ORs) with 95% confidence intervals (CIs). Eleven eligible studies were included. The results showed that compared with IV polymyxins monotherapy, IV plus aerosolised polymyxins therapy significantly reduced all-cause mortality rate (OR = 0.75, 95% CI 0.57-0.99, P = 0.045) and improved clinical improvement rate (OR = 1.62, 95% CI 1.02-2.60, P = 0.043) and microbial eradication rate (OR = 2.07, 95% CI 1.40-3.05, P = 0.000). However, there were no significant differences in terms of clinical cure rate (OR = 1.59, 95% CI 0.96-2.63, P = 0.072) and nephrotoxicity (OR = 1.14, 95% CI 0.80-1.63, P = 0.467) for IV plus aerosolised polymyxins therapy. Subgroup analysis revealed that the clinical improvement rate was significantly improved in case-control studies. Aerosolised polymyxins may be a useful adjunct to IV polymyxins for patients with CR-GNB VAP.