Microbiological Results Research Articles

Epidemiology, microbiological, clinical characteristics, and outcome of Burkholderia cepacia complex infections in non-cystic fibrosis adult patients from Qatar

ObjectivesBurkholderia species infections are associated with diverse and challenging clinical presentations because of distinct virulence and antimicrobial resistance factors. The study aims to evaluate the epidemiology, microbiological, and clinical outcomes of Burkholderia cepacia complex (Bcc) infections in non-cystic fibrosis (CF) patients from Qatar. MethodsA retrospective study was conducted on adult patients across all hospitals at Hamad Medical Corporation between January 2012 and December 2018 to evaluate clinically relevant Bcc in non-CF adult patients. ResultsOver 7 years, 72 episodes of Burkholderia species infections were recorded, 64 were secondary to Bcc primarily affecting males (78.12%) with a mean age of 53 years, from the Middle and Southeastern region (92.2%) affected predominantly by diabetes mellitus (34.4%), chronic kidney (23.4%), coronary heart (20.3%), and hypertensive diseases (17.2%) while recent hospitalization and admission to critical care were evident in 45.3% and 93.8% of cases, respectively. Main infection sites were urinary (43.8%) and respiratory (29.7%) with associated bacteremia recorded in 26.6% of cases. Microbiological characteristics demonstrated high-level resistance profiles leading to delayed microbiological clearance in case of bacteremia (61%) and management with multiple therapeutic agents (range 4-6) resulting in disease resolution in 90.6% of cases with observed 30-day mortality of 7.8%. ConclusionsB. cepacia infections are infrequent, recorded mainly in middle-aged males with chronic comorbidities presenting as urinary, respiratory, and bacteremia associated with hospitalization, admission to critical care, and invasive procedures. High-level antimicrobial resistance is observed necessitating multiple therapeutic agents and suboptimal bacteriological clearance.

Clinical Outcomes for Patients With Monomicrobial vs Polymicrobial Acinetobacter baumannii-calcoaceticus Complex Infections Treated With Sulbactam-Durlobactam or Colistin: A Subset Analysis From a Phase 3 Clinical Trial.

In a previous study, the efficacy and safety of sulbactam-durlobactam vs colistin for the treatment of patients with carbapenem-resistant Acinetobacter baumannii-calcoaceticus complex (CRABC) infections were evaluated in a randomized controlled phase 3 trial. Both arms were dosed on a background of imipenem-cilastatin to treat coinfecting gram-negative pathogens. Thirty-six percent of infections in the primary efficacy population were polymicrobial. A subset analysis was performed to compare clinical and microbiological outcomes at test of cure (7 ± 2 days after the last dose) for patients with monomicrobial and polymicrobial CRABC infections. Minimal inhibitory concentrations of antibiotics against baseline isolates were determined by broth microdilution according to Clinical and Laboratory Standards Institute methodology. Clinical cure, 28-day all-cause mortality, and microbiological outcomes were similar for patients in the sulbactam-durlobactam treatment arm with monomicrobial or polymicrobial A baumannii-calcoaceticus infections. Patients in the colistin arm with monomicrobial CRABC infections had higher mortality rates with worse clinical and microbiological outcomes as compared with those with polymicrobial infections. For patients who received sulbactam-durlobactam, imipenem susceptibility of coinfecting gram-negative pathogens trended with clinical benefit for patients with polymicrobial A baumannii-calcoaceticus infections. When tested in vitro, durlobactam restored imipenem susceptibility to the majority of coinfecting gram-negative pathogens from the sulbactam-durlobactam arm. This phenotype appeared to be related to the clinical outcome in 13 of 15 evaluable cases. These results suggest that the use of sulbactam-durlobactam plus a carbapenem could be an effective approach to treat polymicrobial infections that include CRABC, but additional clinical data are needed to demonstrate efficacy.

Clinical Characteristics and Microorganisms Isolated in Community-Acquired Pneumonia in the COVID-19 Period.

Community-acquired pneumonia is a leading cause of mortality and hospital admissions. The aetiology remains unknown in 30-65% of the cases. Molecular tests are available for multiple pathogen detection and are under research to improve the causal diagnosis. We carried out a prospective study to describe the clinical characteristics and aetiology of community-acquired pneumonia during the COVID-19 pandemic and to assess the diagnostic effectivity of the microbiological tests, including a molecular test of respiratory pathogens (FilmArray™ bioMérieux). From the 1st of February 2021 until the 31st of March 2022, 225 patients were included. Failure in microorganism identification occurred in approximately 70% of patients. Streptococcus pneumoniae was the most common isolate. There were 5 cases of viral pneumonia. The tested FilmArray exhibited a low positivity rate of 7% and mainly aided in the diagnosis of viral coinfections. Despite our extensive diagnostic protocol, there is still a low rate of microorganism identification. We have observed a reduction in influenza and other viral pneumoniae during the COVID-19 pandemic. Having a high NEWS2 score on arrival at the emergency department, an active oncohematological disease or chronic neurological conditions and a positive microbiological test result were related to worse outcomes. Further research is needed to determine the role of molecular tests in the microbiological diagnosis of pneumonia.

The Clinical Efficacy of Adding Ceftazidime/Avibactam to Standard Therapy in Treating Infections Caused by Carbapenem-Resistant Klebsiella pneumonia with blaOXA-48-like Genes.

Ceftazidime/avibactam (CAZ-AVI) is FDA-approved for managing infections caused by resistant gram-negative bacilli, particularly infections via carbapenem-resistant Enterobacterales pathogens. The clinical data are still limited, particularly those in Saudi Arabia. The present study is a retrospective cohort study that was carried out at the Armed Forces Hospital in the southern region of Saudi Arabia to compare the clinical and microbiological outcomes for CAZ-AVI-treated patients as monotherapy and as an add-on to standard therapy for carbapenem-resistant Klebsiella pneumonia (CRKP) OXA-48 infections to those treated with standard drugs. The study included CRKP OXA-48-like infected patients who were administered antibiotics for more than seven days from 1 August 2018 to May 2023. Patients' baseline characteristics and demography were extracted from the clinical records, and their clinical/microbiology efficiencies were assessed as per the corresponding definitions. Univariate and multivariate logistic regressions were conducted to identify the potential independent variable for CAZ-AVI efficiency. A total of 114 patient files were included for the evaluation. Among these patients, 64 used CAZ-AVI combined with standard therapy and were included in the intervention group, and 50 of them used standard therapy and were included in the comparative group. Following analysis, CAZ-AVI's clinical success was 42.2% (p = 0.028), while the intervention versus comparative groups showed decreased 30-day all-cause mortality (50.0% versus 70.0%; p = 0.036) and infection recurrence (7.8% versus 24.0%; p = 0.019), as well as substantially increased rates of microbial eradication (68.8% versus 42.0%; p = 0.007). CAZ-AVI add-on therapy rather than monotherapy showed statistically significant favored clinical and microbial outcomes over the standard therapy. Furthermore, sex (female %), ICU admission, and fever were negatively associated with patients' 30-day all-cause mortality, serving as independent negative factors. Only fever, CRP bio levels, inotropes, and ICU admissions were significant predictors influencing the CAZ-AVI's clinical efficiency. The duration of CAZ-AVI therapy positively influenced CAZ-AVI's microbial eradication, while both WBC counts and fever experiences were negative predictors. This study shows the effective usage of CAZ-AVI against CRKP OXA-48-like infections. The influencing independent variables depicted here should recommend that clinicians individualize the CAZ-AVI dose based on co-existing risk factors to achieve optimal survival and efficacy. Prospective multicenter and randomized control studies are recommended, with individualized CAZ-AVI precision administration implemented based on patients' characteristics.

BACTERIOLOGICAL STUDY OF VENTILATOR-ASSOCIATED PNEUMONIA AND ANTIBIOTIC SUSCEPTIBILITY OF ISOLATES

Objective: The present study determined the prevalence of various aerobic bacteria causing ventilator-associated pneumonia in adult patients. Initially the bacteria causing ventilator-associated pneumonia was isolated from ET samples and studied the antimicrobial susceptibility pattern of bacterial isolates.
 Methods: Total 250 endotracheal aspiration (ET) samples were collected from patients admitted in Medical, Respiratory and Surgical ICUs for 1 y period. ET aspirates were collected under aseptic precautions and processed as per standard operating procedure for the identification of microorganisms. The antibiotic susceptibility test was performed by using Kirby-Bauer disk diffusion method as per CLSI guidelines.
 Results: Out of the 250 samples processed, culture-positive were 34.8% (n=87) and culture-negative were 65.2% (n=163). Out of 87 culture-positive samples, polymicrobial growth was observed in 9.19% (n=8) and monomicrobial growth was observed in 90.8% (n=79). Gram negative bacilli 95.7% (n=91), and gram-positive cocci isolates are 4.2% (n=4). Among Gram-negative organisms isolated, A. baumannii is the most common isolate 33 (34.7%), followed by P. aeruginosa 28 (29.5%) and K. pneumoniae 20 (21.0%) E. coli 8 (8.4%) and E. cloacae 2 (2.1%). Out of 4 Gram-positive organisms isolated, 3 (3.1%) were MSSA, and 1(1.1%) was MRSA.
 Conclusion: VAP is increasingly associated with multidrug-resistant (MDR) pathogens due to the production of ESBL, Amp C b-lactamase, Metallo-b-lactamase. It is important to carry out aggressive surveillance to determine the prevalence of MDR organisms and to generate a local antibiogram periodically. Early and appropriate antibiotics in right doses followed by de-escalation based on microbiological culture results are essential to curtail the VAP rate. VAP bundle care shall be implemented correctly.

Estimation of the shelf life of sweetened soft drinks based on microbiological and sensory analysis

In the present investigation, the shelf life of sweetened beverages was investigated through microbiological and sensory analyses. An experimental design was employed, which included the variable of storage time. This allowed for the identification of significant differences in the organoleptic and microbiological characteristics of the beverages. Samples of the beverages were taken during their processing and evaluated over time, especially during the pasteurization process at 85°C for 120 seconds. Laboratory analyses focused on microbiological tests, sensory studies, and assessments of the processed product's quality. The microbiological results remained within the limits established by INEN standards, with counts of mesophilic aerobes < 100 CFU/cm3, yeasts and molds < 50 CFU/cm3, total coliforms < 3 MPN/cm3, and fecal coliforms < 3 MPN/cm3. Regarding sensory analysis, it was found that the beverages had a characteristic aroma, a slightly yellow color, and a characteristic citrus flavor, making them highly acceptable to consumers. Furthermore, the shelf life of the beverages was determined through accelerated aging at 32°C, resulting in a shelf life of 2 months. These findings supported the conclusion that the beverages could be stored for 6 months at room temperature, as indicated in another study that employed a similar methodology and evaluated properties such as color, aroma, and flavor. Keywords: Analysis, mesophilic aerobes, fecal coliforms, yeasts and fungi4 , shelf life

Estimation of the shelf life of sweetened soft drinks based on microbiological and sensory analysis

In the present investigation, the shelf life of sweetened beverages was investigated through microbiological and sensory analyses. An experimental design was employed, which included the variable of storage time. This allowed for the identification of significant differences in the organoleptic and microbiological characteristics of the beverages. Samples of the beverages were taken during their processing and evaluated over time, especially during the pasteurization process at 85°C for 120 seconds. Laboratory analyses focused on microbiological tests, sensory studies, and assessments of the processed product's quality. The microbiological results remained within the limits established by INEN standards, with counts of mesophilic aerobes < 100 CFU/cm3, yeasts and molds < 50 CFU/cm3, total coliforms < 3 MPN/cm3, and fecal coliforms < 3 MPN/cm3. Regarding sensory analysis, it was found that the beverages had a characteristic aroma, a slightly yellow color, and a characteristic citrus flavor, making them highly acceptable to consumers. Furthermore, the shelf life of the beverages was determined through accelerated aging at 32°C, resulting in a shelf life of 2 months. These findings supported the conclusion that the beverages could be stored for 6 months at room temperature, as indicated in another study that employed a similar methodology and evaluated properties such as color, aroma, and flavor. Keywords: Analysis, mesophilic aerobes, fecal coliforms, yeasts and fungi4 , shelf life

Reprocessed Single-Use Semicritical and Critical Medical Devices

What Is the Issue?
 
 Reprocessing a medical device includes cleaning, reconditioning, testing, and disinfection to ensure the device can safely be reused. In contrast to reusable medical devices, manufacturers are not required to provide instructions for properly cleaning and sterilizing single-use medical devices (SUMDs).
 Health Canada regulates third-party device reprocessors and requires they meet the same requirements as new device manufacturers. Health Canada does not provide oversight for hospital onsite reprocessing, deferring to the oversight provided at the provincial and territorial levels. Given the potential economic and environmental benefits of using reprocessed SUMDs, there is a growing interest in determining the clinical safety of reprocessed SUMDs.
 Current standards for reprocessing medical devices use definitions for sterilization and disinfection based on measurement of bioburden, but not necessarily clinical outcomes such as infection.
 
 What Did We Do?
 
 To inform decisions about the appropriate use of reprocessed critical and semicritical SUMDs, CADTH sought to identify and summarize literature evaluating the clinical safety of reprocessed SUMDs, defined as infections, mortality, or other adverse events, compared with nonreprocessed (new) SUMDs. Microbiological outcomes, such as bacterial colony counts, were not included. An information specialist searched for peer-reviewed and grey literature sources.
 This report does not provide a comprehensive list of device reprocessors in Canada or recommend any specific methods of reprocessing medical devices.
 
 What Did We Find?
 
 We identified 8 studies, including one study based in Canada, that evaluated the use of reprocessed SUMDs compared with new SUMDs; most did not report statistically significant differences in patient outcomes between groups.
 Most of the included studies were of very low to moderate quality, which limits confidence in the observed outcomes resulting from the reuse of these devices. Half of the included studies were published before the year 2005, which may limit applicability given potential improvements and changes over time in reprocessing standards, surgical approaches, device specifications, and patient care protocols.
 Most of the studies evaluated a different type of reprocessed single-use medical device for different surgical populations, so there is very limited evidence for the use of a specific device in a specific population or intervention of interest. All included studies evaluated SUMDs classified as critical, and all were conducted in surgical settings; however, it is unclear whether patient risk levels would be different for semicritical devices or in nonsurgical settings.
 
 What Does it Mean?
 
 Given various devices, clinical applications, and reprocessing methods, it is difficult to draw broad conclusions about the appropriateness of reprocessing SUMDs.
 While the evidence base in this review was insufficient to conclude whether reprocessed critical SUMDs in surgical settings affect patient outcomes, Canadian standards and other resources exist to help inform decisions around medical device reprocessing based on infection risk.
 To ensure patient safety, any reprocessing of SUMDs should meet standards for safety, effectiveness, and labelling that follow Health Canada regulations.

Automated surveillance of non-ventilator-associated hospital-acquired pneumonia (nvHAP): a systematic literature review

BackgroundHospital-acquired pneumonia (HAP) and its specific subset, non-ventilator hospital-acquired pneumonia (nvHAP) are significant contributors to patient morbidity and mortality. Automated surveillance systems for these healthcare-associated infections have emerged as a potentially beneficial replacement for manual surveillance. This systematic review aims to synthesise the existing literature on the characteristics and performance of automated nvHAP and HAP surveillance systems.MethodsWe conducted a systematic search of publications describing automated surveillance of nvHAP and HAP. Our inclusion criteria covered articles that described fully and semi-automated systems without limitations on patient demographics or healthcare settings. We detailed the algorithms in each study and reported the performance characteristics of automated systems that were validated against specific reference methods. Two published metrics were employed to assess the quality of the included studies.ResultsOur review identified 12 eligible studies that collectively describe 24 distinct candidate definitions, 23 for fully automated systems and one for a semi-automated system. These systems were employed exclusively in high-income countries and the majority were published after 2018. The algorithms commonly included radiology, leukocyte counts, temperature, antibiotic administration, and microbiology results. Validated surveillance systems' performance varied, with sensitivities for fully automated systems ranging from 40 to 99%, specificities from 58 and 98%, and positive predictive values from 8 to 71%. Validation was often carried out on small, pre-selected patient populations.ConclusionsRecent years have seen a steep increase in publications on automated surveillance systems for nvHAP and HAP, which increase efficiency and reduce manual workload. However, the performance of fully automated surveillance remains moderate when compared to manual surveillance. The considerable heterogeneity in candidate surveillance definitions and reference standards, as well as validation on small or pre-selected samples, limits the generalisability of the findings. Further research, involving larger and broader patient populations is required to better understand the performance and applicability of automated nvHAP surveillance.

Application of a multiplex molecular pneumonia panel and real-world impact on antimicrobial stewardship among patients with hospital-acquired and ventilator-associated pneumonia in intensive care units

BackgroundThe optimal timing for applying the BioFire FilmArray Pneumonia Panel (FAPP) in intensive care unit (ICU) patients with hospital-acquired pneumonia (HAP) or ventilator-associated pneumonia (VAP) remains undefined, and there are limited data on its impact on antimicrobial stewardship. MethodsThis retrospective study was conducted at a referral hospital in Taiwan from November 2019 to October 2022. Adult ICU patients with HAP/VAP who underwent FAPP testing were enrolled. Patient data, FAPP results, conventional microbiological testing results, and the real-world impact of FAPP results on antimicrobial therapy adjustments were assessed. Logistic regression was used to determine the predictive factors for bacterial detection by FAPP. ResultsAmong 592 respiratory specimens, including 564 (95.3%) endotracheal aspirate specimens, 19 (3.2%) expectorated sputum specimens and 9 (1.5%) bronchoalveolar lavage specimens, from 467 patients with HAP/VAP, FAPP testing yielded 368 (62.2%) positive results. Independent predictors for positive bacterial detection by FAPP included prolonged hospital stay (odds ratio [OR], 3.14), recent admissions (OR, 1.59), elevated C-reactive protein levels (OR, 1.85), Acute Physiology and Chronic Health Evaluation II scores (OR, 1.58), and septic shock (OR, 1.79). Approximately 50% of antimicrobial therapy for infections caused by Gram-negative bacteria and 58.4% for Gram-positive bacteria were adjusted or confirmed after obtaining FAPP results. ConclusionsThis study identified several factors predicting bacterial detection by FAPP in critically ill patients with HAP/VAP. More than 50% real-world clinical practices were adjusted or confirmed based on the FAPP results. Clinical algorithms for the use of FAPP and antimicrobial stewardship guidelines may further enhance its benefits.

Paediatric cancer patients with severe sepsis or septic shock at the PICU with positive microbiological results do worse than those with negative results: a retrospective cohort study

PurposeInfections are a leading cause of mortality and morbidity in paediatric cancer patients. The aim of this study was to determine whether positive or negative microbiological results impact the clinical outcomes of sepsis in paediatric cancer patients admitted to the paediatric intensive care unit (PICU).MethodsWe performed a retrospective observational single-centre cohort study between 1 January 2018 and 31 December 2020 in the Netherlands. All paediatric cancer patients aged 0 to 18 years admitted to PICU due to severe sepsis or septic shock were included.ResultsWe identified 73 PICU admissions in 58 unique patients. Forty-nine of the 73 PICU admissions (67.1%) had positive blood and/or bronchoalveolar lavage microbiological results. Patients with positive results had a higher Paediatric Logistic Organ Dysfunction-2 (PELOD-2) score at PICU admission compared to patients with negative results (median (IQR), 7 (6–9) vs 6 (4–8), p = 0.04). Mortality in PICU among patients with positive results was significantly higher when compared to patients with negative results, 18% versus 0% respectively (p = 0.03). In addition, patients with positive results had significantly less ventilator-free days at day 28 compared to patients with negative results, median (IQR) 26 (19–28) versus 28 (27–28) respectively (p = 0.01).ConclusionsMicrobiologically confirmed infections (bacterial, viral, or fungal) in paediatric cancer patients with sepsis are associated with higher mortality in PICU and a higher need for PICU resources. Large-scale (multicentre) studies in paediatric oncologic patients are required to confirm these results.

Carbapenem-resistant Enterobacterales among hospitalized patients in Cape Town, South Africa: clinical and microbiological epidemiology.

Carbapenem-resistant Enterobacterales (CRE) are a substantial problem in Cape Town. CRE epidemiology is largely unknown and mortality remains high. To describe and characterize the clinical and microbiological epidemiology of CRE within Cape Town hospitals to better inform therapy with regard to current and novel antibiotics, as well as improve antimicrobial stewardship (AMS), and infection prevention and control (IPC). This prospective, multicentre study performed between 1 November 2020 and 30 November 2022, across three public and three private hospitals included hospitalized participants with CRE from clinical cultures. Participant demographics, clinical information and microbiology results were collected and analysed. Ninety percent of participants were from public hospitals. The age distribution ranged from 7 days to 88 years. Notable risk factors for CRE infection included recent exposure to antibiotics, medical devices and surgery. The most prevalent species was Klebsiella pneumoniae. However, a higher proportion of Serratia marcescens compared with previous reports was identified. The detected carbapenemases were blaOXA-48-like (80%) and blaNDM (11%). With the exception of amikacin (63%), tigecycline (65%), colistin (95%) and ceftazidime/avibactam (87%), susceptibility to antibiotics was low. This study identified common risk factors for CRE infection and generated a description of carbapenemase enzymes, species distribution and antibiograms, enabling a better understanding of CRE epidemiology. This provides insights into transmission patterns and resistance determinants of CREs, beneficial to informing data-driven regional patient management, AMS and IPC strategies.

Optimal selection of specimens for metagenomic next-generation sequencing in diagnosing periprosthetic joint infections.

This study aimed to assess the diagnostic value of metagenomic next-generation sequencing (mNGS) across synovial fluid, prosthetic sonicate fluid, and periprosthetic tissues among patients with periprosthetic joint infection (PJI), intending to optimize specimen selection for mNGS in these patients. This prospective study involved 61 patients undergoing revision arthroplasty between September 2021 and September 2022 at the First Affiliated Hospital of Zhengzhou University. Among them, 43 cases were diagnosed as PJI, and 18 as aseptic loosening (AL) based on the American Musculoskeletal Infection Society (MSIS) criteria. Preoperative or intraoperative synovial fluid, periprosthetic tissues, and prosthetic sonicate fluid were collected, each divided into two portions for mNGS and culture. Comparative analyses were conducted between the microbiological results and diagnostic efficacy derived from mNGS and culture tests. Furthermore, the variability in mNGS diagnostic efficacy for PJI across different specimen types was assessed. The sensitivity and specificity of mNGS diagnosis was 93% and 94.4% for all types of PJI specimens; the sensitivity and specificity of culture diagnosis was 72.1% and 100%, respectively. The diagnostic sensitivity of mNGS was significantly higher than that of culture (X2 = 6.541, P=0.011), with no statistically significant difference in specificity (X2 = 1.029, P=0.310). The sensitivity of the synovial fluid was 83.7% and the specificity was 94.4%; the sensitivity of the prosthetic sonicate fluid was 90.7% and the specificity was 94.4%; and the sensitivity of the periprosthetic tissue was 81.4% and the specificity was 100%. Notably, the mNGS of prosthetic sonicate fluid displayed a superior pathogen detection rate compared to other specimen types. mNGS can function as a precise diagnostic tool for identifying pathogens in PJI patients using three types of specimens. Due to its superior ability in pathogen identification, prosthetic sonicate fluid can replace synovial fluid and periprosthetic tissue as the optimal sample choice for mNGS.

Association between Clinical Characteristics and Microbiota in Bronchiectasis Patients Based on Metagenomic Next-Generation Sequencing Technology.

This study aimed to investigate the disparities between metagenomic next-generation sequencing (mNGS) and conventional culture results in patients with bronchiectasis. Additionally, we sought to investigate the correlation between the clinical characteristics of patients and their microbiome profiles. The overarching goal was to enhance the effective management and treatment of bronchiectasis patients, providing a theoretical foundation for healthcare professionals. A retrospective survey was conducted on 67 bronchiectasis patients admitted to The First Hospital of Jiaxing from October 2019 to March 2023. Clinical baseline information, inflammatory indicators, and pathogen detection reports, including mNGS, conventional blood culture, bronchoalveolar lavage fluid (BALF) culture, and sputum culture results, were collected. By comparing the results of mNGS and conventional culture, the differences in pathogen detection rate and pathogen types were explored, and the diagnostic performance of mNGS compared to conventional culture was evaluated. Based on the various pathogens detected by mNGS, the association between clinical characteristics of bronchiectasis patients and mNGS microbiota results was analyzed. The number and types of pathogens detected by mNGS were significantly larger than those detected by conventional culture. The diagnostic efficacy of mNGS was significantly superior to conventional culture for all types of pathogens, particularly in viral detection (p < 0.01). Regarding pathogen detection rate, the bacteria with the highest detection rate were Pseudomonas aeruginosa (17/58) and Haemophilus influenzae (11/58); the fungus with the highest detection rate was Aspergillus fumigatus (10/21), and the virus with the highest detection rate was human herpes virus 4 (4/11). Differences were observed between the positive and negative groups for P. aeruginosa in terms of common scoring systems for bronchiectasis and whether the main symptom of bronchiectasis manifested as thick sputum (p < 0.05). Significant distinctions were also noted between the positive and negative groups for A. fumigatus regarding Reiff score, neutrophil percentage, bronchiectasis etiology, and alterations in treatment plans following mNGS results reporting (p < 0.05). Notably, 70% of patients with positive A. fumigatus infection opted to change their treatment plans. The correlation study between clinical characteristics of bronchiectasis patients and mNGS microbiological results revealed that bacteria, such as P. aeruginosa, and fungi, such as A. fumigatus, were associated with specific clinical features of patients. This underscored the significance of mNGS in guiding personalized treatment approaches. mNGS could identify multiple pathogens in different types of bronchiectasis samples and was a rapid and effective diagnostic tool for pathogen identification. Its use was recommended for diagnosing the causes of infections in bronchiectasis patients.

Knowledge, Perception, and Self-Confidence of Antibiotic Resistance, Appropriate Antibiotic Therapy, and Antibiotic Stewardship Among Undergraduate Pharmacy Students in Sudan.

Adequate training in infectious diseases and antibiotic resistance is crucial for pharmacy students to participate in antibiotic stewardship programs and understand microbiology careers. The study was carried out to assess the knowledge and self-reported confidence in antibiotic resistance, antibiotic therapy, and antimicrobial stewardship (AMS) among final-year undergraduate pharmacy students in Sudan. A cross-sectional study was conducted in three universities using a 57-item online questionnaire between April and May 2022. A total of 109 students (response rate 36%) participated and showed average knowledge scores of 5.6±1.7 (out of 10.0) for antibiotic resistance, 4.9±2.0 (out of 5.0) for appropriate antibiotic therapy, and 3.1±1.4 (out of 5.0) for AMS. No significant differences were observed among schools. Some students reported poor knowledge about antibiotic therapy and the consequences of resistance. One-third of students lacked confidence in interpreting microbiological results. Knowledge of antibiotic resistance among students' practice area after graduation was higher (p=0.017) and those interested in ID careers (5.8 vs 4.8) (p=0.037). Male students (5.6 vs 4.5) and those interested in ID careers (4.3 vs 3.4) (p<0.001) had higher scores of appropriate antibiotic therapy. Students attended antibiotic resistance courses (51.5 vs 45.2), and those interested in ID significantly had higher self-confidence (55.3 vs 45.8) (p=0.008). Pharmacy students in Sudan have substantial knowledge of AMS and antibiotic resistance with poor knowledge of antibiotic therapy. Adequate training about infectious diseases and related topics is recommended to improve pharmacy students' understanding of microbiological findings, other competencies, and skills to incorporate in antimicrobial stewardship.

Study of Colistin Resistant Gram Negative Organism in Hospitalized Patients: A Retrospective Study.

Intensive care units have become hotspots for antimicrobial resistance, particularly concerning colistin resistance, posing a threat of untreatable infections. This study aims to analyze the epidemiological and clinical aspects of patients carrying colistin-resistant organisms. It focuses on identifying risk factors, the microbiological profile, susceptibility patterns, and treatment outcomes. Isolates with colistin MIC >2 µg/mL, identified via BD PHOENIX, were subjected to colistin broth disc elution testing (as per CLSI guidelines) in our Microbiology Department between January and December 2022. Among the 30 patients, colistin-resistant gram-negative isolates were found predominantly in blood cultures (50%), followed by ET/TT cultures (23.3%), urine cultures (10%), and other sites (16.7%). Klebsiella pneumoniae was the most common organism (80%), showing the highest sensitivity to Ceftazidime-avibactam + Aztreonam (CAZ-AVI + ATM) (76.7%). Of these patients, 66.7% recovered and were discharged, while 33.3% succumbed during hospitalization despite treatment. The study underscores a notable presence of colistin-resistant gram-negative isolates, predominantly in blood cultures, with K. pneumoniae being predominant. The combination of CAZ-AVI + ATM exhibited the highest sensitivity. However, the mortality rate of 33.3% despite sensitive antibiotic treatment highlights the urgency for ongoing vigilance and research to combat colistin-resistant infections and improve patient outcomes. Diwane D, Rajhans PA, Jog SA, Dalvi M. Study of Colistin Resistant Gram Negative Organism in Hospitalized Patients: A Retrospective Study. Indian J Crit Care Med 2024;28(3):286-289.

Comparison of disease and economic burden between MRSA infection and MRSA colonization in a university hospital: a retrospective data integration study

BackgroundAlthough there is a growing concern and policy regarding infections or colonization caused by resistant bacteria, including methicillin-resistant Staphylococcus aureus (MRSA), the prognosis of MRSA infections compared to that of methicillin-susceptible Staphylococcus aureus (MSSA) infections remains controversial. Moreover, there have not been any studies comparing both the burden of disease and its impact on the healthcare economy between MRSA infection and colonization while adjusting for confounding factors. These comparisons are crucial for developing effective infection control measures and healthcare policies. We aimed to compare the disease and economic burden between MRSA and MSSA infections and between MRSA infection and colonization.MethodsWe retrospectively investigated data of 496 in-patients with MRSA or MSSA infections and of 1178 in-patients with MRSA infections or MRSA colonization from a university hospital in Japan from 2016 to 2021. We compared in-hospital mortality, length of stay, and hospital charges between in-patients with MRSA and MSSA infections and those with MRSA infections and MRSA colonization using multiple regressions. We combined surveillance data, including all microbiological test results, data on patients with infections, treatment histories, and clinical outcomes, to create the datasets.ResultsThere was no statistically significant difference in in-hospital mortality rates between matched MRSA vs. MSSA infections and MRSA infection vs. colonization. On the contrary, the adjusted effects of the MRSA infection compared to those of MSSA infection on length of stay and hospital charges were 1.21-fold (95% confidence interval [CI] 1.03–1.42, P = 0.019) and 1.70-fold (95% CI 1.39–2.07, P < 0.00001), respectively. The adjusted effects of the MRSA infection compared to those of MRSA colonization on length of stay and hospital charges were 1.41-fold (95% CI 1.25–1.58, P < 0.00001) and 1.53-fold (95% CI 1.33–1.75, P < 0.00001), respectively. Regarding confounding factors, hemodialysis or hemofiltration was consistently identified and adjusted for in the multiple regression analyses comparing MRSA and MSSA infections, as well as MRSA infection and MRSA colonization.ConclusionsMRSA infection was associated with longer length of stay and higher hospital charges than both MSSA infection and MRSA colonization. Furthermore, hemodialysis or hemofiltration was identified as a common underlying factor contributing to increased length of stay and hospital charges.

GeneXpert MTB/RIF Ultra vs Unstimulated Interferon γ (IRISA-TB) for the Diagnosis of Tuberculous Pericarditis in a Tuberculosis-Endemic Setting.

Tuberculous pericarditis (TBP) is a paucibacillary disease, where host biomarkers such as unstimulated interferon γ (IRISA-TB) have high diagnostic accuracy. However, DNA-based diagnostic tests (GeneXpert Ultra), more sensitive than an earlier versions, have recently become available. Given that the diagnosis of TBP is challenging, we performed a comparative diagnostic accuracy study comparing both assays. We recruited 99 consecutive patients with suspected TBP in Cape Town, South Africa. Definite TBP was defined by microbiological confirmation of tuberculosis (TB) on pericardial fluid culture or an alternative polymerase chain reaction-based test (GeneXpert MTB/RIF) or by use of sputum (polymerase chain reaction or culture). Probable TBP was defined as a high clinical suspicion of TB accompanied by anti-TB treatment, while non-TBP was defined as negative microbiological test results for TB without initiation of TB treatment and/or the presence of an alternative diagnosis. There were 39 patients with definite TBP, 35 with probable TBP, and 23 with non-TBP. Approximately 70% of participants who received TB treatment were HIV coinfected. Overall, IRISA-TB was more sensitive than Xpert Ultra (88.6% [95% CI, 74.1%-95.5%] vs 71.5% [55.0%-83.7%], n = 53) and significantly more sensitive in participants who were HIV uninfected (100% [95% CI, 72.3%-100.0%] vs 60% [31.3%-83.2%], P = .03). In patients with definite and probable TBP combined (n = 84), sensitivity was significantly higher with IRISA-TB (77.3% [95% CI, 65.9%-85.8%] vs 37.9 [27.2%-50.0%], P < .0001). A similar pattern was seen in persons who were HIV uninfected (88.3% vs 35.3%, P = .002). Specificity was high for both assays (>95%). Unstimulated interferon γ (IRISA-TB) was significantly more sensitive than Xpert Ultra for the diagnosis of TB pericarditis in a TB-endemic resource-poor setting.

Microbial, chemical, and isotopic monitoring integrated approach to assess potential leachate contamination of groundwater in a karstic aquifer (Apulia, Italy)

Landfill sites are subjected to long-term risks of accidental spill of leachate through the soil and consequential contamination of the groundwater. Wide areas surrounding the landfill can seriously be threatened with possible consequences to human health and the environment. Given the potential impact of different coexisting anthropic pollution sources (i.e., agriculture and cattle farming) on the same site, the perturbation of the groundwater quality may be due to multiple factors. Therefore, it is a challenging issue to correctly establish the pollution source of an aquifer where the landfill is not isolated from other anthropic land uses, especially in the case of a karstic coastal aquifer. The present study is aimed at setting in place an integrated environmental monitoring system that included microbiological, chemical, and isotope methods to evaluate potential groundwater pollution in a landfill district in the south of Italy located in Murgia karstic aquifer. Conventional (microbial plate count and physical–chemical analyses) and advanced methods (PCR-ARISA, isotope analysis of δ18O, δ2H, 3H, δ 13C, δ 15N-NO3−, and δ 18O-NO3−) were included in the study. Through data integration, it was possible to reconstruct a scenario in which agriculture and other human activities along with seawater intrusion in the karst aquifer were the main drivers of groundwater pollution at the monitored site. The microbiological, chemical, and isotope results confirmed the absence of leachate effects on groundwater quality, showing the decisive role of fertilizers as potential nitrate sources. The next goal will be to extend long-term integrated monitoring to other landfill districts, with different geological and hydrogeological characteristics and including different sources of pollution, to support the ecological restoration of landfills.

Immediate vs. culture-initiated antibiotic therapy in suspected non-severe ventilator-associated pneumonia: a before–after study (DELAVAP)

BackgroundVentilator-associated pneumonia (VAP) is the leading nosocomial infection in critical care and is associated with adverse outcomes. When VAP is suspected, starting antibiotic therapy (AT) immediately after pulmonary sampling may expose uninfected patients to unnecessary treatment, whereas waiting for bacteriological confirmation may delay AT in infected patients. As no robust data exist to choose between these strategies, the decision must balance the pre-test diagnostic probability, clinical severity, and risk of antimicrobial resistance. The objective of this study in patients with suspected non-severe VAP was to compare immediate AT started after sampling to conservative AT upon receipt of positive microbiological results. The outcomes were antibiotic sparing, AT suitability, and patient outcomes.MethodsThis single-center, before–after study included consecutive patients who underwent distal respiratory sampling for a first suspected non-severe VAP episode (no shock requiring vasopressor therapy or severe acute respiratory distress syndrome). AT was started immediately after sampling in 2019 and upon culture positivity in 2022 (conservative strategy). The primary outcome was the number of days alive without AT by day 28. The secondary outcomes were mechanical ventilation duration, day-28 mortality, and AT suitability (active necessary AT or spared AT).ResultsThe immediate and conservative strategies were applied in 44 and 43 patients, respectively. Conservative and immediate AT were associated with similar days alive without AT (median [interquartile range], 18.0 [0–21.0] vs. 16.0 [0–20.0], p = 0.50) and without broad-spectrum AT (p = 0.53) by day 28. AT was more often suitable in the conservative group (88.4% vs. 63.6%, p = 0.01), in which 27.9% of patients received no AT at all. No significant differences were found for mechanical ventilation duration (median [95%CI], 9.0 [6–19] vs. 9.0 [6–24] days, p = 0.65) or day-28 mortality (hazard ratio [95%CI], 0.85 [0.4–2.0], p = 0.71).ConclusionIn patients with suspected non-severe VAP, waiting for microbiological confirmation was not associated with antibiotic sparing, compared to immediate AT. This result may be ascribable to low statistical power. AT suitability was better with the conservative strategy. None of the safety outcomes differed between groups. These findings would seem to allow a large, randomized trial comparing immediate and conservative AT strategies.